diff --git a/CMakeLists.txt b/CMakeLists.txt
index 63a74bc1..53b67bde 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -16,19 +16,51 @@ option( USE_MPEG    "enable video recording with FFmpeg, uses libavcodec" OFF )
 option( INTEL_MIC        "cross compile for intel xeon phi")
 option( INSTALL_PROFILES "install environment variable settings to /etc/profile.d" OFF )
 option( USE_CCACHE       "use ccache")
+option( USE_INTERNAL_TCL "Compile tcl files into the code and don't install them" ON)
 
 option( USE_SUPERBUILD       "use ccache" ON)
 
 set(CMAKE_MODULE_PATH "${CMAKE_MODULE_PATH}" "${CMAKE_CURRENT_SOURCE_DIR}/cmake/cmake_modules")
 
+if(APPLE)
+  set(INSTALL_DIR_DEFAULT /Applications/Netgen.app)
+else(APPLE)
+  if(WIN32)
+    set(INSTALL_DIR_DEFAULT "C:/netgen")
+  else(WIN32)
+    set(INSTALL_DIR_DEFAULT /opt/netgen)
+  endif(WIN32)
+endif(APPLE)
+
+if(INSTALL_DIR)
+  message(WARNING "INSTALL_DIR is deprecated, use CMAKE_INSTALL_PREFIX instead")
+  set(INSTALL_DIR_DEFAULT ${INSTALL_DIR})
+endif(INSTALL_DIR)
+
+if(UNIX)
+  message("Checking for write permissions in install directory...")
+  execute_process(COMMAND mkdir -p ${CMAKE_INSTALL_PREFIX})
+  execute_process(COMMAND test -w ${CMAKE_INSTALL_PREFIX} RESULT_VARIABLE res)
+  if(res)
+    message(WARNING "No write access at install directory, please set correct permissions")
+  endif()
+endif(UNIX)
+
 if (USE_SUPERBUILD)
   project (SUPERBUILD)
+  if (CMAKE_INSTALL_PREFIX_INITIALIZED_TO_DEFAULT)
+    set(CMAKE_INSTALL_PREFIX "${INSTALL_DIR_DEFAULT}" CACHE PATH "Install directory" FORCE)
+  endif()
+
   # execute the superbuild (this script will be invoked again without the
   # USE_SUPERBUILD option this time)
   include (cmake/SuperBuild.cmake)
   return()                      # stop processing this file further
 else()
   project(Netgen)
+  if (CMAKE_INSTALL_PREFIX_INITIALIZED_TO_DEFAULT)
+    set(CMAKE_INSTALL_PREFIX "${INSTALL_DIR_DEFAULT}" CACHE PATH "Install directory" FORCE)
+  endif()
 endif()
 
 set(NETGEN_VERSION_MAJOR 6)
@@ -68,43 +100,68 @@ if (ADDITIONAL_PATHS)
   set(CMAKE_PREFIX_PATH ${ADDITIONAL_PATHS})
 endif (ADDITIONAL_PATHS)
 
-if(APPLE)
-  set(CMAKE_INSTALL_PREFIX "${INSTALL_DIR}/Contents/Resources" CACHE INTERNAL "Prefix prepended to install directories" FORCE)
-else(APPLE)
-  set(CMAKE_INSTALL_PREFIX "${INSTALL_DIR}" CACHE INTERNAL "Prefix prepended to install directories" FORCE) 
-endif(APPLE)
-
-#######################################################################
-# use rpath
-SET(CMAKE_SKIP_BUILD_RPATH  FALSE)
-SET(CMAKE_BUILD_WITH_INSTALL_RPATH FALSE) 
-SET(CMAKE_INSTALL_RPATH "${CMAKE_INSTALL_PREFIX}/lib")
-SET(CMAKE_INSTALL_RPATH_USE_LINK_PATH TRUE)
-LIST(FIND CMAKE_PLATFORM_IMPLICIT_LINK_DIRECTORIES "${CMAKE_INSTALL_PREFIX}/lib" isSystemDir)
-IF("${isSystemDir}" STREQUAL "-1")
-   SET(CMAKE_INSTALL_RPATH "${CMAKE_INSTALL_PREFIX}/lib")
-ENDIF("${isSystemDir}" STREQUAL "-1")
-
 #######################################################################
 # build options
-add_definitions(-DUSE_TIMEOFDAY)
-
 include_directories ("${PROJECT_SOURCE_DIR}/include")
 include_directories ("${PROJECT_SOURCE_DIR}/libsrc/include")
 include_directories ("${PROJECT_BINARY_DIR}")
 
 set(CMAKE_INCLUDE_CURRENT_DIR ON)
 
-set(INCDIR include CACHE PATH "install directory for header files")
 if(APPLE)
-  set(ng_install_dir_bin ../MacOS)
-  set(ng_install_dir_lib ../MacOS)
+  set(NG_INSTALL_DIR_BIN_DEFAULT Contents/MacOS)
+  set(NG_INSTALL_DIR_LIB_DEFAULT Contents/MacOS)
+  set(NG_INSTALL_DIR_CMAKE_DEFAULT Contents/Resources/share/cmake)
+  set(NG_INSTALL_DIR_PYTHON_DEFAULT Contents/Resources/${PYTHON_PACKAGES_INSTALL_DIR})
+  set(NG_INSTALL_DIR_RES_DEFAULT Contents/Resources/share)
+  set(NG_INSTALL_DIR_INCLUDE_DEFAULT Contents/Resources/include)
+
+  set(NG_RPATH_TOKEN "@loader_path")
 else(APPLE)
-  set(ng_install_dir_bin bin)
-  set(ng_install_dir_lib lib)
+  set(NG_INSTALL_DIR_BIN_DEFAULT bin)
+  set(NG_INSTALL_DIR_LIB_DEFAULT lib)
+  set(NG_INSTALL_DIR_CMAKE_DEFAULT lib/cmake)
+  set(NG_INSTALL_DIR_PYTHON_DEFAULT ${PYTHON_PACKAGES_INSTALL_DIR})
+  set(NG_INSTALL_DIR_RES_DEFAULT share)
+  set(NG_INSTALL_DIR_INCLUDE_DEFAULT include)
+
+  set(NG_RPATH_TOKEN "\$ORIGIN")
 endif(APPLE)
-set(ng_install_dir EXPORT netgen-targets RUNTIME DESTINATION ${ng_install_dir_bin} COMPONENT netgen LIBRARY DESTINATION ${ng_install_dir_lib} COMPONENT netgen_devel ARCHIVE DESTINATION ${ng_install_dir_lib} COMPONENT netgen_devel)
-install(EXPORT netgen-targets DESTINATION share/cmake)
+
+set(NG_INSTALL_SUFFIX netgen CACHE STRING "Suffix appended to install directories (project name)")
+set(NG_INSTALL_DIR_PYTHON ${NG_INSTALL_DIR_PYTHON_DEFAULT} CACHE STRING "Install directory for Python files")
+set(NG_INSTALL_DIR_BIN ${NG_INSTALL_DIR_BIN_DEFAULT} CACHE STRING "Install directory for executables")
+set(NG_INSTALL_DIR_LIB ${NG_INSTALL_DIR_LIB_DEFAULT} CACHE STRING "Install directory for libraries")
+set(NG_INSTALL_DIR_INCLUDE ${NG_INSTALL_DIR_INCLUDE_DEFAULT} CACHE STRING "Install directory for header files")
+set(NG_INSTALL_DIR_CMAKE ${NG_INSTALL_DIR_CMAKE_DEFAULT} CACHE STRING "Install directory for CMake files")
+set(NG_INSTALL_DIR_RES ${NG_INSTALL_DIR_RES_DEFAULT} CACHE STRING "Install directory for resources")
+
+get_filename_component(NETGEN_CMAKE_DIR_ABSOLUTE ${NG_INSTALL_DIR_CMAKE} ABSOLUTE BASE_DIR ${CMAKE_INSTALL_PREFIX})
+get_filename_component(NETGEN_BINARY_DIR_ABSOLUTE ${NG_INSTALL_DIR_BIN} ABSOLUTE BASE_DIR ${CMAKE_INSTALL_PREFIX})
+get_filename_component(NETGEN_LIBRARY_DIR_ABSOLUTE ${NG_INSTALL_DIR_LIB} ABSOLUTE BASE_DIR ${CMAKE_INSTALL_PREFIX})
+get_filename_component(NETGEN_INCLUDE_DIR_ABSOLUTE ${NG_INSTALL_DIR_INCLUDE} ABSOLUTE BASE_DIR ${CMAKE_INSTALL_PREFIX})
+get_filename_component(NETGEN_PYTHON_DIR_ABSOLUTE ${NG_INSTALL_DIR_PYTHON} ABSOLUTE BASE_DIR ${CMAKE_INSTALL_PREFIX})
+get_filename_component(NETGEN_RESOURCE_DIR_ABSOLUTE ${NG_INSTALL_DIR_RES} ABSOLUTE BASE_DIR ${CMAKE_INSTALL_PREFIX})
+
+file(RELATIVE_PATH NETGEN_DIR ${NETGEN_CMAKE_DIR_ABSOLUTE} ${CMAKE_INSTALL_PREFIX})
+file(RELATIVE_PATH NETGEN_BINARY_DIR ${NETGEN_CMAKE_DIR_ABSOLUTE} ${NETGEN_BINARY_DIR_ABSOLUTE})
+file(RELATIVE_PATH NETGEN_LIBRARY_DIR ${NETGEN_CMAKE_DIR_ABSOLUTE} ${NETGEN_LIBRARY_DIR_ABSOLUTE})
+file(RELATIVE_PATH NETGEN_INCLUDE_DIR ${NETGEN_CMAKE_DIR_ABSOLUTE} ${NETGEN_INCLUDE_DIR_ABSOLUTE})
+file(RELATIVE_PATH NETGEN_PYTHON_DIR ${NETGEN_CMAKE_DIR_ABSOLUTE} ${NETGEN_PYTHON_DIR_ABSOLUTE})
+file(RELATIVE_PATH NETGEN_RESOURCE_DIR ${NETGEN_CMAKE_DIR_ABSOLUTE} ${NETGEN_RESOURCE_DIR_ABSOLUTE})
+
+file(RELATIVE_PATH NETGEN_RPATH ${NETGEN_BINARY_DIR_ABSOLUTE} ${NETGEN_LIBRARY_DIR_ABSOLUTE})
+file(RELATIVE_PATH NETGEN_PYTHON_RPATH_BIN ${NETGEN_PYTHON_DIR_ABSOLUTE} ${NETGEN_BINARY_DIR_ABSOLUTE})
+file(RELATIVE_PATH NETGEN_PYTHON_RPATH ${NETGEN_PYTHON_DIR_ABSOLUTE} ${NETGEN_LIBRARY_DIR_ABSOLUTE})
+if(WIN32)
+	set(NETGEN_PYTHON_RPATH ${NETGEN_PYTHON_RPATH_BIN})
+endif(WIN32)
+
+set(NG_INSTALL_DIR EXPORT netgen-targets RUNTIME DESTINATION ${NG_INSTALL_DIR_BIN} COMPONENT netgen LIBRARY DESTINATION ${NG_INSTALL_DIR_LIB} COMPONENT netgen_devel ARCHIVE DESTINATION ${NG_INSTALL_DIR_LIB} COMPONENT netgen_devel)
+install(EXPORT netgen-targets DESTINATION ${NG_INSTALL_DIR_CMAKE} )
+
+set(CMAKE_MACOSX_RPATH TRUE)
+set(CMAKE_INSTALL_RPATH "${NG_RPATH_TOKEN};${NG_RPATH_TOKEN}/${NETGEN_RPATH}")
 
 include (CheckIncludeFiles)
 check_include_files (dlfcn.h HAVE_DLFCN_H)
@@ -185,8 +242,8 @@ if (USE_PYTHON)
     include_directories(${PYBIND_INCLUDE_DIR})
     include_directories(${PYTHON_INCLUDE_DIRS})
 
-    install(DIRECTORY ${PYBIND_INCLUDE_DIR}/pybind11 DESTINATION ${INCDIR} COMPONENT netgen_devel)
-    install(FILES ${PYBIND_INCLUDE_DIR}/../LICENSE DESTINATION ${INCDIR}/pybind11 COMPONENT netgen_devel)
+    install(DIRECTORY ${PYBIND_INCLUDE_DIR}/pybind11 DESTINATION ${NG_INSTALL_DIR_INCLUDE} COMPONENT netgen_devel)
+    install(FILES ${PYBIND_INCLUDE_DIR}/../LICENSE DESTINATION ${NG_INSTALL_DIR_INCLUDE}/pybind11 COMPONENT netgen_devel)
 endif (USE_PYTHON)
 
 #######################################################################
@@ -222,10 +279,10 @@ endif (USE_MPEG)
 #######################################################################
 if(INSTALL_PROFILES)
     file(WRITE  ${CMAKE_CURRENT_BINARY_DIR}/netgen.sh "#!/bin/sh\n")
-    file(APPEND ${CMAKE_CURRENT_BINARY_DIR}/netgen.sh "export PATH=${INSTALL_DIR}/bin:$PATH\n")
-    file(APPEND ${CMAKE_CURRENT_BINARY_DIR}/netgen.sh "export NETGENDIR=${INSTALL_DIR}/bin\n")
-    file(APPEND ${CMAKE_CURRENT_BINARY_DIR}/netgen.sh "export PYTHONPATH=${INSTALL_DIR}/${PYTHON_PACKAGES_INSTALL_DIR}:.\n")
-    file(APPEND ${CMAKE_CURRENT_BINARY_DIR}/netgen.sh "export LD_LIBRARY_PATH=${INSTALL_DIR}/lib:.\n")
+    file(APPEND ${CMAKE_CURRENT_BINARY_DIR}/netgen.sh "export PATH=${CMAKE_INSTALL_PREFIX}/bin:$PATH\n")
+    file(APPEND ${CMAKE_CURRENT_BINARY_DIR}/netgen.sh "export NETGENDIR=${CMAKE_INSTALL_PREFIX}/bin\n")
+    file(APPEND ${CMAKE_CURRENT_BINARY_DIR}/netgen.sh "export PYTHONPATH=${CMAKE_INSTALL_PREFIX}/${PYTHON_PACKAGES_INSTALL_DIR}:.\n")
+    file(APPEND ${CMAKE_CURRENT_BINARY_DIR}/netgen.sh "export LD_LIBRARY_PATH=${CMAKE_INSTALL_PREFIX}/lib:.\n")
     install(PROGRAMS ${CMAKE_CURRENT_BINARY_DIR}/netgen.sh DESTINATION /etc/profile.d COMPONENT netgen)
 
     string(ASCII 27 Esc)
@@ -237,19 +294,19 @@ endif(INSTALL_PROFILES)
 #######################################################################
 file(WRITE ${CMAKE_CURRENT_BINARY_DIR}/fixup.cmake "\
 include(${CMAKE_CURRENT_SOURCE_DIR}/cmake/netgen_fixup.cmake)
-set(APP ${INSTALL_DIR})
+set(APP ${CMAKE_INSTALL_PREFIX})
 message(\${APP})
 set(BU_CHMOD_BUNDLE_ITEMS ON)
 
-file(GLOB libs ${CMAKE_INSTALL_PREFIX}/${ng_install_dir_lib}/*.dylib ${CMAKE_INSTALL_PREFIX}/${ng_install_dir_lib}/*.so)
+file(GLOB libs ${CMAKE_INSTALL_PREFIX}/${NG_INSTALL_DIR_LIB}/*.dylib ${CMAKE_INSTALL_PREFIX}/${NG_INSTALL_DIR_LIB}/*.so)
 message(\"\${libs}\")
-netgen_fixup_bundle( \${APP}/Contents/MacOS/netgen \"\${libs}\" ${CMAKE_INSTALL_PREFIX}/${ng_install_dir_lib} )
-execute_process(COMMAND ln -s /Applications ${INSTALL_DIR}/../Applications)
+netgen_fixup_bundle( \${APP}/Contents/MacOS/netgen \"\${libs}\" ${CMAKE_INSTALL_PREFIX}/${NG_INSTALL_DIR_LIB} )
+execute_process(COMMAND ln -s /Applications ${CMAKE_INSTALL_PREFIX}/../Applications)
 set (bundle_filename \$ENV{NETGEN_BUNDLE_NAME})
 if(NOT bundle_filename)
   set(bundle_filename netgen)
 endif(NOT bundle_filename)
-execute_process(COMMAND hdiutil create -volname Netgen -srcfolder ${INSTALL_DIR} -ov -format UDZO \${bundle_filename}-${PACKAGE_VERSION}.dmg)
+execute_process(COMMAND hdiutil create -volname Netgen -srcfolder ${CMAKE_INSTALL_PREFIX} -ov -format UDZO \${bundle_filename}-${PACKAGE_VERSION}.dmg)
 ")
   add_custom_target(bundle COMMAND ${CMAKE_COMMAND} "-P" "${CMAKE_CURRENT_BINARY_DIR}/fixup.cmake")
 #######################################################################
@@ -323,7 +380,7 @@ export PYTHONPATH=$Netgen_BUNDLE/Contents/Resources/${PYTHON_PACKAGES_INSTALL_DI
 cd $Netgen_MACOS
 $Netgen_MACOS/netgen
 ")
-    install(PROGRAMS ${mac_startup} DESTINATION ${ng_install_dir_bin})
+    install(PROGRAMS ${mac_startup} DESTINATION ${NG_INSTALL_DIR_BIN})
 
     set(mac_ngsuite ${CMAKE_CURRENT_BINARY_DIR}/ngsuite.sh)
     file(WRITE ${mac_ngsuite} "\
@@ -332,7 +389,7 @@ Netgen_BUNDLE=\"`echo \"$0\" | sed -e 's/\\/Contents\\/MacOS\\/Netgen1//'`\"
 Netgen_MACOS=\"$Netgen_BUNDLE/Contents/MacOS\"
 open -a /Applications/Utilities/Terminal.app $Netgen_MACOS/startup.sh
 ")
-    install(PROGRAMS ${mac_ngsuite} DESTINATION ../MacOS RENAME Netgen1)
+    install(PROGRAMS ${mac_ngsuite} DESTINATION ${NG_INSTALL_DIR_BIN} RENAME Netgen1)
 
     set(mac_plist ${CMAKE_CURRENT_BINARY_DIR}/Info.plist)
     file(WRITE ${mac_plist} "<?xml version=\"1.0\" encoding=\"UTF-8\"?>
@@ -350,8 +407,8 @@ open -a /Applications/Utilities/Terminal.app $Netgen_MACOS/startup.sh
 </dict>
 </plist>
 ")
-    install(FILES ${mac_plist} DESTINATION ../)
-    install(FILES ${CMAKE_CURRENT_SOURCE_DIR}/netgen.icns DESTINATION . RENAME Netgen.icns)
+    install(FILES ${mac_plist} DESTINATION ${NG_INSTALL_DIR_BIN}/../)
+    install(FILES ${CMAKE_CURRENT_SOURCE_DIR}/netgen.icns DESTINATION ${NG_INSTALL_DIR_RES}/../ RENAME Netgen.icns)
 
 endif(APPLE)
 
@@ -368,10 +425,14 @@ configure_file(
 add_custom_target(uninstall
     COMMAND ${CMAKE_COMMAND} -P ${CMAKE_CURRENT_BINARY_DIR}/cmake_uninstall.cmake)
 
+#######################################################################
+# Generate package config file
+get_directory_property(NETGEN_COMPILE_DEFINITIONS COMPILE_DEFINITIONS)
+
 configure_file(${CMAKE_CURRENT_SOURCE_DIR}/cmake/NetgenConfig.cmake.in
 	${CMAKE_CURRENT_BINARY_DIR}/NetgenConfig.cmake @ONLY)
 
-install(FILES ${CMAKE_CURRENT_BINARY_DIR}/NetgenConfig.cmake DESTINATION share/cmake)
+install(FILES ${CMAKE_CURRENT_BINARY_DIR}/NetgenConfig.cmake DESTINATION ${NG_INSTALL_DIR_CMAKE})
 
 #######################################################################
 # Configure message
diff --git a/cmake/NetgenConfig.cmake.in b/cmake/NetgenConfig.cmake.in
index c72d40c3..9cfa7da7 100644
--- a/cmake/NetgenConfig.cmake.in
+++ b/cmake/NetgenConfig.cmake.in
@@ -1,7 +1,17 @@
 set(PACKAGE_VERSION "@NETGEN_VERSION@")
-set(NETGEN_DIR "@CMAKE_INSTALL_PREFIX@")
 
-set(NETGEN_INCLUDE_DIR "@CMAKE_INSTALL_PREFIX@/@INCDIR@")
+get_filename_component(NETGEN_CMAKE_DIR "${CMAKE_CURRENT_LIST_FILE}" PATH)
+
+set(NETGEN_DIR "${NETGEN_CMAKE_DIR}/@NETGEN_DIR@")
+
+set(NETGEN_COMPILE_DEFINITIONS "@NETGEN_COMPILE_DEFINITIONS@")
+
+set(NETGEN_INCLUDE_DIR "${NETGEN_CMAKE_DIR}/@NETGEN_INCLUDE_DIR@/include;${NETGEN_CMAKE_DIR}/@NETGEN_INCLUDE_DIR@")
+set(NETGEN_BINARY_DIR "${NETGEN_CMAKE_DIR}/@NETGEN_BINARY_DIR@")
+set(NETGEN_LIBRARY_DIR "${NETGEN_CMAKE_DIR}/@NETGEN_LIBRARY_DIR@")
+set(NETGEN_PYTHON_DIR "${NETGEN_CMAKE_DIR}/@NETGEN_PYTHON_DIR@")
+set(NETGEN_RESOURCE_DIR "${NETGEN_CMAKE_DIR}/@NETGEN_RESOURCE_DIR@")
+
 set(NETGEN_SOURCE_DIR "@PROJECT_SOURCE_DIR@")
 
 set(NETGEN_CMAKE_THREAD_LIBS_INIT "@CMAKE_THREAD_LIBS_INIT@")
@@ -14,7 +24,6 @@ set(NETGEN_METIS_LIBRARY "@METIS_LIBRARY@")
 set(NETGEN_MKL_LIBRARIES "@MKL_LIBRARIES@")
 set(NETGEN_MPI_CXX_INCLUDE_PATH "@MPI_CXX_INCLUDE_PATH@")
 set(NETGEN_MPI_CXX_LIBRARIES "@MPI_CXX_LIBRARIES@")
-set(NETGEN_INCLUDE_DIRS "@CMAKE_INSTALL_PREFIX@/@INCDIR@;@CMAKE_INSTALL_PREFIX@/@INCDIR@/include")
 set(NETGEN_OCC_INCLUDE_DIR "@OCC_INCLUDE_DIR@")
 set(NETGEN_OCC_LIBRARIES_BIN "@OCC_LIBRARIES_BIN@")
 set(NETGEN_OCC_LIBRARIES "@OCC_LIBRARIES@")
@@ -46,4 +55,4 @@ set(NETGEN_INSTALL_PROFILES @INSTALL_PROFILES@)
 set(NETGEN_USE_CCACHE @USE_CCACHE@)
 
 include(${CMAKE_CURRENT_LIST_DIR}/netgen-targets.cmake)
-message(STATUS "Found Netgen: ${NETGEN_DIR}")
+message(STATUS "Found Netgen: ${CMAKE_CURRENT_LIST_DIR}")
diff --git a/cmake/SuperBuild.cmake b/cmake/SuperBuild.cmake
index b802b6fa..91ede9e7 100644
--- a/cmake/SuperBuild.cmake
+++ b/cmake/SuperBuild.cmake
@@ -40,19 +40,10 @@ if(WIN32)
   endif(${CMAKE_SIZEOF_VOID_P} MATCHES 4)
 endif(WIN32)
 
-#######################################################################
-# find netgen
-if(APPLE)
-  set(INSTALL_DIR /Applications/Netgen.app CACHE PATH "Install path")
-  set(CMAKE_INSTALL_PREFIX "${INSTALL_DIR}/Contents/Resources" CACHE INTERNAL "Prefix prepended to install directories" FORCE)
-else(APPLE)
-  set(INSTALL_DIR /opt/netgen CACHE PATH "Install path")
-  set(CMAKE_INSTALL_PREFIX "${INSTALL_DIR}" CACHE INTERNAL "Prefix prepended to install directories" FORCE)
-endif(APPLE)
 if(UNIX)
   message("Checking for write permissions in install directory...")
-  execute_process(COMMAND mkdir -p ${INSTALL_DIR})
-  execute_process(COMMAND test -w ${INSTALL_DIR} RESULT_VARIABLE res)
+  execute_process(COMMAND mkdir -p ${CMAKE_INSTALL_PREFIX})
+  execute_process(COMMAND test -w ${CMAKE_INSTALL_PREFIX} RESULT_VARIABLE res)
   if(res)
     message(WARNING "No write access at install directory, please set correct permissions")
   endif()
@@ -94,7 +85,7 @@ if(USE_OCC AND WIN32 AND NOT OCC_INCLUDE_DIR)
       BUILD_IN_SOURCE 1
       CONFIGURE_COMMAND ""
       BUILD_COMMAND ""
-      INSTALL_COMMAND ${CMAKE_COMMAND} -E copy_directory . ${INSTALL_DIR}
+      INSTALL_COMMAND ${CMAKE_COMMAND} -E copy_directory . ${CMAKE_INSTALL_PREFIX}
       LOG_DOWNLOAD 1
       )
     list(APPEND NETGEN_DEPENDENCIES win_download_occ)
@@ -140,10 +131,11 @@ set_vars( NETGEN_CMAKE_ARGS
   USE_NATIVE_ARCH
   USE_OCC
   USE_MPEG
-  INSTALL_DIR
+  USE_INTERNAL_TCL
   INSTALL_PROFILES
   INTEL_MIC
   CMAKE_PREFIX_PATH
+  CMAKE_INSTALL_PREFIX
   )
 
 # propagate all variables set on the command line using cmake -DFOO=BAR
@@ -166,7 +158,7 @@ endif()
 ExternalProject_Add (netgen
   DEPENDS ${NETGEN_DEPENDENCIES}
   SOURCE_DIR ${PROJECT_SOURCE_DIR}
-  CMAKE_ARGS -DUSE_SUPERBUILD=OFF ${NETGEN_CMAKE_ARGS} -DCMAKE_PREFIX_PATH=${INSTALL_DIR}
+  CMAKE_ARGS -DUSE_SUPERBUILD=OFF ${NETGEN_CMAKE_ARGS}
   INSTALL_COMMAND ""
   BINARY_DIR ${CMAKE_CURRENT_BINARY_DIR}/netgen
   BUILD_COMMAND ${NETGEN_BUILD_COMMAND}
@@ -176,21 +168,21 @@ ExternalProject_Add (netgen
 # Check if the git submodules (i.e. pybind11) are up to date
 # in case, something is wrong, emit a warning but continue
  ExternalProject_Add_Step(netgen check_submodules
-   COMMAND cmake -P ${CMAKE_CURRENT_SOURCE_DIR}/cmake/check_submodules.cmake
+   COMMAND ${CMAKE_COMMAND} -P ${CMAKE_CURRENT_SOURCE_DIR}/cmake/check_submodules.cmake
    DEPENDERS install # Steps on which this step depends
    )
 
 # Due to 'ALWAYS 1', this step is always run which also forces a build of
 # the Netgen subproject
  ExternalProject_Add_Step(netgen check_submodules1
-   COMMAND cmake -P ${CMAKE_CURRENT_SOURCE_DIR}/cmake/check_submodules.cmake
+   COMMAND ${CMAKE_COMMAND} -P ${CMAKE_CURRENT_SOURCE_DIR}/cmake/check_submodules.cmake
    DEPENDEES configure # Steps on which this step depends
    DEPENDERS build     # Steps that depend on this step
    ALWAYS 1            # No stamp file, step always runs
    )
 
 
-install(CODE "execute_process(COMMAND cmake --build . --target install --config ${CMAKE_BUILD_TYPE} WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}/netgen)")
+install(CODE "execute_process(COMMAND ${CMAKE_COMMAND} --build . --target install --config ${CMAKE_BUILD_TYPE} WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}/netgen)")
 
 add_custom_target(test_netgen
   ${CMAKE_COMMAND} --build ${CMAKE_CURRENT_BINARY_DIR}/netgen
diff --git a/cmake/external_projects/tcltk.cmake b/cmake/external_projects/tcltk.cmake
index 65d06df0..6be407b3 100644
--- a/cmake/external_projects/tcltk.cmake
+++ b/cmake/external_projects/tcltk.cmake
@@ -61,7 +61,7 @@ elseif(WIN32)
     BUILD_IN_SOURCE 1
     CONFIGURE_COMMAND ""
     BUILD_COMMAND ""
-    INSTALL_COMMAND ${CMAKE_COMMAND} -E copy_directory . ${INSTALL_DIR}
+    INSTALL_COMMAND ${CMAKE_COMMAND} -E copy_directory . ${CMAKE_INSTALL_PREFIX}
     LOG_DOWNLOAD 1
     )
 
diff --git a/doc/CMakeLists.txt b/doc/CMakeLists.txt
index d7563fdb..e45555c7 100644
--- a/doc/CMakeLists.txt
+++ b/doc/CMakeLists.txt
@@ -1 +1 @@
-INSTALL(FILES ng4.pdf DESTINATION doc COMPONENT netgen_doc)
+INSTALL(FILES ng4.pdf DESTINATION ${NG_INSTALL_DIR_RES}/${NG_INSTALL_SUFFIX}/doc COMPONENT netgen_doc)
diff --git a/libsrc/csg/CMakeLists.txt b/libsrc/csg/CMakeLists.txt
index 510b0e09..224a48e4 100644
--- a/libsrc/csg/CMakeLists.txt
+++ b/libsrc/csg/CMakeLists.txt
@@ -14,7 +14,7 @@ endif(APPLE)
 if(NOT WIN32)
     target_link_libraries(csg mesh ${PYTHON_LIBRARIES})
     target_link_libraries(csg ${PYTHON_LIBRARIES})
-    install( TARGETS csg ${ng_install_dir})
+    install( TARGETS csg ${NG_INSTALL_DIR})
 endif(NOT WIN32)
 
 
@@ -25,7 +25,7 @@ if(USE_GUI)
         if(APPLE)
             set_target_properties( csgvis PROPERTIES SUFFIX ".so")
         endif(APPLE)
-        install( TARGETS csgvis ${ng_install_dir})
+        install( TARGETS csgvis ${NG_INSTALL_DIR})
     endif(NOT WIN32)
 endif(USE_GUI)
 
@@ -36,5 +36,5 @@ install(FILES
   polyhedra.hpp revolution.hpp singularref.hpp solid.hpp
   specpoin.hpp spline3d.hpp splinesurface.hpp surface.hpp
   triapprox.hpp vscsg.hpp
-  DESTINATION ${INCDIR}/csg COMPONENT netgen_devel
+  DESTINATION ${NG_INSTALL_DIR_INCLUDE}/csg COMPONENT netgen_devel
 )
diff --git a/libsrc/general/CMakeLists.txt b/libsrc/general/CMakeLists.txt
index 811bc80d..5faf7c6c 100644
--- a/libsrc/general/CMakeLists.txt
+++ b/libsrc/general/CMakeLists.txt
@@ -8,7 +8,7 @@ add_library(gen OBJECT
 
 set_target_properties( gen PROPERTIES POSITION_INDEPENDENT_CODE ON )
 
-install( FILES ngexception.hpp DESTINATION ${INCDIR} COMPONENT netgen_devel )
+install( FILES ngexception.hpp DESTINATION ${NG_INSTALL_DIR_INCLUDE} COMPONENT netgen_devel )
 
 install(FILES
   archive_base.hpp array.hpp autodiff.hpp autoptr.hpp bitarray.hpp
@@ -17,5 +17,5 @@ install(FILES
   optmem.hpp parthreads.hpp profiler.hpp seti.hpp sort.hpp
   spbita2d.hpp stack.hpp symbolta.hpp table.hpp template.hpp
   gzstream.h
-  DESTINATION ${INCDIR}/general COMPONENT netgen_devel
+  DESTINATION ${NG_INSTALL_DIR_INCLUDE}/general COMPONENT netgen_devel
 )
diff --git a/libsrc/geom2d/CMakeLists.txt b/libsrc/geom2d/CMakeLists.txt
index 332fe06f..299157af 100644
--- a/libsrc/geom2d/CMakeLists.txt
+++ b/libsrc/geom2d/CMakeLists.txt
@@ -6,19 +6,19 @@ endif(APPLE)
 
 if(NOT WIN32)
     target_link_libraries(geom2d mesh ${PYTHON_LIBRARIES})
-    install( TARGETS geom2d ${ng_install_dir})
+    install( TARGETS geom2d ${NG_INSTALL_DIR})
 endif(NOT WIN32)
 
 if(USE_GUI)
     add_library(geom2dvis ${NG_LIB_TYPE} vsgeom2d.cpp)
     if(NOT WIN32)
         target_link_libraries(geom2dvis geom2d)
-        install( TARGETS geom2dvis ${ng_install_dir})
+        install( TARGETS geom2dvis ${NG_INSTALL_DIR})
     endif(NOT WIN32)
 endif(USE_GUI)
 
 install(FILES
   geom2dmesh.hpp geometry2d.hpp spline2d.hpp
   splinegeometry2.hpp vsgeom2d.hpp
-  DESTINATION ${INCDIR}/geom2d COMPONENT netgen_devel
+  DESTINATION ${NG_INSTALL_DIR_INCLUDE}/geom2d COMPONENT netgen_devel
 )
diff --git a/libsrc/gprim/CMakeLists.txt b/libsrc/gprim/CMakeLists.txt
index 4bf13c68..3957476a 100644
--- a/libsrc/gprim/CMakeLists.txt
+++ b/libsrc/gprim/CMakeLists.txt
@@ -10,5 +10,5 @@ install(FILES
   adtree.hpp geom2d.hpp geom3d.hpp geomfuncs.hpp geomobjects2.hpp
   geomobjects.hpp geomops2.hpp geomops.hpp geomtest3d.hpp gprim.hpp
   splinegeometry.hpp spline.hpp transform3d.hpp
-  DESTINATION ${INCDIR}/gprim COMPONENT netgen_devel
+  DESTINATION ${NG_INSTALL_DIR_INCLUDE}/gprim COMPONENT netgen_devel
 )
diff --git a/libsrc/include/CMakeLists.txt b/libsrc/include/CMakeLists.txt
index 1bd3dc2f..2be510cf 100644
--- a/libsrc/include/CMakeLists.txt
+++ b/libsrc/include/CMakeLists.txt
@@ -1,10 +1,10 @@
-install(FILES nginterface.h nginterface_v2.hpp DESTINATION ${INCDIR} COMPONENT netgen_devel)
+install(FILES nginterface.h nginterface_v2.hpp DESTINATION ${NG_INSTALL_DIR_INCLUDE} COMPONENT netgen_devel)
 
 install(FILES
   acisgeom.hpp csg.hpp geometry2d.hpp gprim.hpp incopengl.hpp
   inctcl.hpp incvis.hpp linalg.hpp meshing.hpp myadt.hpp mydefs.hpp
   mystdlib.h nginterface_v2_impl.hpp occgeom.hpp ngsimd.hpp
   opti.hpp parallel.hpp parallelinterface.hpp stlgeom.hpp visual.hpp
-  DESTINATION ${INCDIR}/include COMPONENT netgen_devel
+  DESTINATION ${NG_INSTALL_DIR_INCLUDE}/include COMPONENT netgen_devel
   )
 
diff --git a/libsrc/interface/CMakeLists.txt b/libsrc/interface/CMakeLists.txt
index 29213966..ef52c30b 100644
--- a/libsrc/interface/CMakeLists.txt
+++ b/libsrc/interface/CMakeLists.txt
@@ -12,10 +12,10 @@ if(NOT WIN32)
     if(USE_GUI)
         target_link_libraries(interface visual)
     endif(USE_GUI)
-    install( TARGETS interface ${ng_install_dir})
+    install( TARGETS interface ${NG_INSTALL_DIR})
 endif(NOT WIN32)
 
 install(FILES
   writeuser.hpp
-  DESTINATION ${INCDIR}/interface COMPONENT netgen_devel
+  DESTINATION ${NG_INSTALL_DIR_INCLUDE}/interface COMPONENT netgen_devel
 )
diff --git a/libsrc/linalg/CMakeLists.txt b/libsrc/linalg/CMakeLists.txt
index e50fb5b5..a5a5a4f2 100644
--- a/libsrc/linalg/CMakeLists.txt
+++ b/libsrc/linalg/CMakeLists.txt
@@ -7,5 +7,5 @@ set_target_properties(la PROPERTIES POSITION_INDEPENDENT_CODE ON )
 install(FILES
   densemat.hpp linalg.hpp opti.hpp
   polynomial.hpp vector.hpp
-  DESTINATION ${INCDIR}/linalg COMPONENT netgen_devel
+  DESTINATION ${NG_INSTALL_DIR_INCLUDE}/linalg COMPONENT netgen_devel
 )
diff --git a/libsrc/meshing/CMakeLists.txt b/libsrc/meshing/CMakeLists.txt
index 959f2868..e9e6e211 100644
--- a/libsrc/meshing/CMakeLists.txt
+++ b/libsrc/meshing/CMakeLists.txt
@@ -21,6 +21,7 @@ add_library(mesh ${NG_LIB_TYPE}
         topology.cpp triarls.cpp validate.cpp bcfunctions.cpp   
         parallelmesh.cpp  paralleltop.cpp  paralleltop.hpp basegeom.cpp     
         python_mesh.cpp hexarls.cpp
+        ../../ng/onetcl.cpp
         ${mesh_object_libs}
         )
 
@@ -30,7 +31,7 @@ endif(APPLE)
 
 if(NOT WIN32)
     target_link_libraries( mesh ${ZLIB_LIBRARIES} ${MPI_CXX_LIBRARIES} ${PYTHON_LIBRARIES} ${METIS_LIBRARY})
-    install( TARGETS mesh ${ng_install_dir})
+    install( TARGETS mesh ${NG_INSTALL_DIR})
 endif(NOT WIN32)
 
 install(FILES
@@ -42,5 +43,5 @@ install(FILES
   localh.hpp meshclass.hpp meshfunc.hpp meshing2.hpp meshing3.hpp
   meshing.hpp meshtool.hpp meshtype.hpp msghandler.hpp paralleltop.hpp
   ruler2.hpp ruler3.hpp specials.hpp topology.hpp validate.hpp
-  DESTINATION ${INCDIR}/meshing COMPONENT netgen_devel
+  DESTINATION ${NG_INSTALL_DIR_INCLUDE}/meshing COMPONENT netgen_devel
 )
diff --git a/libsrc/meshing/python_mesh.cpp b/libsrc/meshing/python_mesh.cpp
index b4c3f8d3..774aae17 100644
--- a/libsrc/meshing/python_mesh.cpp
+++ b/libsrc/meshing/python_mesh.cpp
@@ -11,6 +11,8 @@
 
 using namespace netgen;
 
+extern const char *ngscript[];
+
 namespace netgen
 {
   extern bool netgen_executable_started;
@@ -51,6 +53,12 @@ static Transformation<3> global_trafo(Vec<3> (0,0,0));
 DLL_HEADER void ExportNetgenMeshing(py::module &m) 
 {
   m.attr("_netgen_executable_started") = py::cast(netgen::netgen_executable_started);
+  string script;
+  const char ** hcp = ngscript;
+  while (*hcp)
+      script += *hcp++;
+
+  m.attr("_ngscript") = py::cast(script);
 
   py::class_<NGDummyArgument>(m, "NGDummyArgument")
     .def("__bool__", []( NGDummyArgument &self ) { return false; } )
diff --git a/libsrc/occ/CMakeLists.txt b/libsrc/occ/CMakeLists.txt
index 8f7f7c32..831f2e6b 100644
--- a/libsrc/occ/CMakeLists.txt
+++ b/libsrc/occ/CMakeLists.txt
@@ -10,10 +10,10 @@ add_library(occvis ${NG_LIB_TYPE} vsocc.cpp)
 if(NOT WIN32)
     target_link_libraries( occ ${OCC_LIBRARIES} ${PYTHON_LIBRARIES})
     target_link_libraries( occvis occ )
-    install( TARGETS occ occvis ${ng_install_dir})
+    install( TARGETS occ occvis ${NG_INSTALL_DIR})
 endif(NOT WIN32)
 
 install(FILES
   occgeom.hpp occmeshsurf.hpp vsocc.hpp
-  DESTINATION ${INCDIR}/occ COMPONENT netgen_devel
+  DESTINATION ${NG_INSTALL_DIR_INCLUDE}/occ COMPONENT netgen_devel
 )
diff --git a/libsrc/stlgeom/CMakeLists.txt b/libsrc/stlgeom/CMakeLists.txt
index d2072a1a..3620c496 100644
--- a/libsrc/stlgeom/CMakeLists.txt
+++ b/libsrc/stlgeom/CMakeLists.txt
@@ -6,7 +6,7 @@ add_library(stl ${NG_LIB_TYPE}
 if(NOT WIN32)
     target_link_libraries( stl mesh  ${PYTHON_LIBRARIES})
     target_link_libraries( stl ${PYTHON_LIBRARIES})
-    install( TARGETS stl ${ng_install_dir})
+    install( TARGETS stl ${NG_INSTALL_DIR})
 endif(NOT WIN32)
 
 if(USE_GUI)
@@ -15,12 +15,12 @@ if(USE_GUI)
             )
     if(NOT WIN32)
         target_link_libraries( stlvis stl )
-        install( TARGETS stlvis ${ng_install_dir})
+        install( TARGETS stlvis ${NG_INSTALL_DIR})
     endif(NOT WIN32)
 endif(USE_GUI)
 
 install(FILES
   meshstlsurface.hpp stlgeom.hpp stlline.hpp
   stltool.hpp stltopology.hpp vsstl.hpp
-  DESTINATION ${INCDIR}/stlgeom COMPONENT netgen_devel
+  DESTINATION ${NG_INSTALL_DIR_INCLUDE}/stlgeom COMPONENT netgen_devel
 )
diff --git a/libsrc/visualization/CMakeLists.txt b/libsrc/visualization/CMakeLists.txt
index 273829a6..8f803d92 100644
--- a/libsrc/visualization/CMakeLists.txt
+++ b/libsrc/visualization/CMakeLists.txt
@@ -1,5 +1,5 @@
 add_definitions(-DNGINTERFACE_EXPORTS)
-install(FILES soldata.hpp DESTINATION ${INCDIR} COMPONENT netgen_devel )
+install(FILES soldata.hpp DESTINATION ${NG_INSTALL_DIR_INCLUDE} COMPONENT netgen_devel )
 
 if(USE_GUI)
     set( LIB_VISUAL_SOURCES meshdoc.cpp mvdraw.cpp vsfieldlines.cpp vsmesh.cpp vssolution.cpp importsolution.cpp )
@@ -11,11 +11,11 @@ add_library(visual ${NG_LIB_TYPE} ${LIB_VISUAL_SOURCES})
 
 if(NOT WIN32)
     target_link_libraries( visual ${PYTHON_LIBRARIES} ${MPI_CXX_LIBRARIES} ${OPENGL_LIBRARIES} )
-    install( TARGETS visual ${ng_install_dir})
+    install( TARGETS visual ${NG_INSTALL_DIR})
 endif(NOT WIN32)
 
 install(FILES
   meshdoc.hpp mvdraw.hpp
   vispar.hpp visual.hpp vssolution.hpp
-  DESTINATION ${INCDIR}/visualization COMPONENT netgen_devel
+  DESTINATION ${NG_INSTALL_DIR_INCLUDE}/visualization COMPONENT netgen_devel
 )
diff --git a/ng/CMakeLists.txt b/ng/CMakeLists.txt
index 9fca6c27..7c4a1f81 100644
--- a/ng/CMakeLists.txt
+++ b/ng/CMakeLists.txt
@@ -1,23 +1,28 @@
-set(gui_sources
-    gui.cpp ngpkg.cpp demoview.cpp parallelfunc.cpp
-    ../libsrc/stlgeom/stlpkg.cpp ../libsrc/visualization/visualpkg.cpp
-    ../libsrc/csg/csgpkg.cpp ../libsrc/geom2d/geom2dpkg.cpp
-    ../libsrc/occ/occpkg.cpp ../libsrc/occ/vsocc.cpp
-  )
+if(USE_INTERNAL_TCL)
+  add_definitions(-DINTERNAL_TCL_DEFAULT=1)
+else()
+  add_definitions(-DINTERNAL_TCL_DEFAULT=0)
+endif()
 
-set(netgen_sources ngappinit.cpp onetcl.cpp )
+set(netgen_sources ngappinit.cpp onetcl.cpp)
+if(WIN32)
+    # add icon to netgen executable
+    enable_language(RC)
+    set(netgen_sources ${netgen_sources} ../windows/netgen.rc)
+    # Don't use ccache here due to incompatiblity with the resource compiler
+    set_directory_properties(PROPERTIES RULE_LAUNCH_COMPILE "")
+endif(WIN32)
 
 if(USE_GUI)
-    if(WIN32)
-      # add icon to netgen executable
-      enable_language(RC)
-      set(netgen_sources ${netgen_sources} ../windows/netgen.rc)
-      # Don't use ccache here due to incompatiblity with the resource compiler
-      set_directory_properties(PROPERTIES RULE_LAUNCH_COMPILE "")
-    endif(WIN32)
 
-    add_library(gui SHARED ${gui_sources})
-    add_executable(netgen ${netgen_sources})
+    add_library(gui SHARED
+        gui.cpp ngpkg.cpp demoview.cpp parallelfunc.cpp
+        ../libsrc/stlgeom/stlpkg.cpp ../libsrc/visualization/visualpkg.cpp
+        ../libsrc/csg/csgpkg.cpp ../libsrc/geom2d/geom2dpkg.cpp
+        ../libsrc/occ/occpkg.cpp ../libsrc/occ/vsocc.cpp
+    )
+
+    add_executable(netgen ngappinit.cpp onetcl.cpp)
 
     target_link_libraries( gui PUBLIC nglib ${ZLIB_LIBRARIES} ${JPEG_LIBRARIES} ${FFMPEG_LIBRARIES} ${X11_X11_LIB} ${OCC_LIBRARIES} )
     target_link_libraries( gui PRIVATE ${LIBTOGL})
@@ -38,8 +43,8 @@ if(USE_GUI)
       target_link_libraries( gui PUBLIC mesh stlvis stl geom2dvis interface geom2d csg stl visual csgvis )
     endif(NOT WIN32)
 
-    install(TARGETS netgen    ${ng_install_dir})
-    install(TARGETS gui ${ng_install_dir})
+    install(TARGETS netgen ${NG_INSTALL_DIR})
+    install(TARGETS gui ${NG_INSTALL_DIR})
 
     if(APPLE)
         set_target_properties(netgen PROPERTIES OUTPUT_NAME netgen)
@@ -59,18 +64,20 @@ if(USE_PYTHON)
         set_target_properties( ngpy PROPERTIES SUFFIX ".pyd")
         set_target_properties( ngpy PROPERTIES OUTPUT_NAME "libngpy")
     endif()
-    install(TARGETS ngpy ${ng_install_dir})
+    set_target_properties(ngpy PROPERTIES INSTALL_RPATH "${NG_RPATH_TOKEN}/../${NETGEN_PYTHON_RPATH}")
+    install(TARGETS ngpy DESTINATION ${NG_INSTALL_DIR_PYTHON}/${NG_INSTALL_SUFFIX})
 endif(USE_PYTHON)
 
 if(USE_GUI)
-  install(FILES
-      dialog.tcl menustat.tcl ngicon.tcl ng.tcl	
-      ngvisual.tcl sockets.tcl nghelp.tcl ngshell.tcl	  
-      ngtesting.tcl parameters.tcl variables.tcl csgeom.tcl stlgeom.tcl 
-      occgeom.tcl acisgeom.tcl netgen.ocf
-      DESTINATION ${ng_install_dir_bin} COMPONENT netgen)
+  if(NOT USE_INTERNAL_TCL)
+    install(FILES
+        dialog.tcl menustat.tcl ngicon.tcl ng.tcl
+        ngvisual.tcl sockets.tcl nghelp.tcl ngshell.tcl
+        ngtesting.tcl parameters.tcl variables.tcl csgeom.tcl stlgeom.tcl
+        occgeom.tcl acisgeom.tcl netgen.ocf drawing.tcl
+        DESTINATION ${NG_INSTALL_DIR_BIN} COMPONENT netgen)
+  endif()
 
   add_subdirectory(Togl2.1)
-  install(FILES drawing.tcl DESTINATION ${ng_install_dir_bin} COMPONENT netgen)
 endif(USE_GUI)
 
diff --git a/ng/Togl2.1/CMakeLists.txt b/ng/Togl2.1/CMakeLists.txt
index 98ae1310..bcade1f7 100644
--- a/ng/Togl2.1/CMakeLists.txt
+++ b/ng/Togl2.1/CMakeLists.txt
@@ -7,7 +7,7 @@ endif(APPLE)
 if(WIN32)
   add_definitions("-DBUILD_togl -DUNICODE -D_UNICODE -DTOGL_USE_FONTS=0 -DSTDC_HEADERS -DSTDC_HEADER")
   add_library(togl SHARED togl.c toglProcAddr.c toglStubInit.c)
-  install(TARGETS togl DESTINATION ${ng_install_dir} COMPONENT netgen)
+  install(TARGETS togl DESTINATION ${NG_INSTALL_DIR} COMPONENT netgen)
   target_link_libraries(togl ${TCL_LIBRARY} ${TK_LIBRARY})
 else(WIN32)
   set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -fomit-frame-pointer -Wno-implicit-int")
diff --git a/ng/ng.tcl b/ng/ng.tcl
index 18a870db..003b745c 100644
--- a/ng/ng.tcl
+++ b/ng/ng.tcl
@@ -1,7 +1,9 @@
 catch {lappend auto_path $env(NETGENDIR) }
 catch {lappend auto_path $env(NETGENDIR)/../lib }
 
-load libgui[info sharedlibextension] gui
+if {[catch {Ng_GetCommandLineParameter batchmode} result ]} {
+	load libgui[info sharedlibextension] gui
+}
 
 set batchmode [Ng_GetCommandLineParameter batchmode]
 if {$batchmode=="undefined"} {
diff --git a/ng/ngappinit.cpp b/ng/ngappinit.cpp
index 21589aaf..a83957a7 100644
--- a/ng/ngappinit.cpp
+++ b/ng/ngappinit.cpp
@@ -191,7 +191,7 @@ int main(int argc, char ** argv)
       // parse tcl-script
       int errcode;
 
-      bool internaltcl = false;
+      bool internaltcl = INTERNAL_TCL_DEFAULT;
       if (shellmode)
         internaltcl = false;
   
diff --git a/ng/onetcl.cpp b/ng/onetcl.cpp
index 5a9df978..53348262 100644
--- a/ng/onetcl.cpp
+++ b/ng/onetcl.cpp
@@ -1,7 +1,9 @@
 const char * ngscript[] = {""
 ,"catch {lappend auto_path $env(NETGENDIR) }\n"
 ,"catch {lappend auto_path $env(NETGENDIR)/../lib }\n"
+,"if {[catch {Ng_GetCommandLineParameter batchmode} result ]} {\n"
 ,"load libgui[info sharedlibextension] gui\n"
+,"}\n"
 ,"set batchmode [Ng_GetCommandLineParameter batchmode]\n"
 ,"if {$batchmode==\"undefined\"} {\n"
 ,"if {[catch {package require tkdnd } result ]} {\n"
@@ -5971,4 +5973,5 @@ const char * ngscript[] = {""
 ,"source startup.tcl }\n"
 ,"catch { source ${ngdir}/demoapp.tcl }\n"
 ,"catch { source ${ngdir}/dropsexp.tcl }\n"
+, nullptr
 };
diff --git a/ng/onetcl.py b/ng/onetcl.py
index f340684b..19f8f546 100644
--- a/ng/onetcl.py
+++ b/ng/onetcl.py
@@ -40,5 +40,6 @@ for line in tclfiles["ng.tcl"].split('\n'):
         s = ',"' + line.replace('\\', r'\\').replace('"', r'\"') + '\\n"\n'
         onetclcpp.write(s)
 
-onetclcpp.write('};'+'\n');
+onetclcpp.write(', nullptr\n');
+onetclcpp.write('};\n');
 onetclcpp.close();
diff --git a/nglib/CMakeLists.txt b/nglib/CMakeLists.txt
index 4a1faee0..ae1bb70c 100644
--- a/nglib/CMakeLists.txt
+++ b/nglib/CMakeLists.txt
@@ -38,5 +38,5 @@ if(USE_PYTHON)
     target_link_libraries(nglib ${PYTHON_LIBRARIES})
 endif(USE_PYTHON)
 
-install(TARGETS nglib ${ng_install_dir})
-install(FILES nglib.h DESTINATION ${INCDIR}/include COMPONENT netgen_devel)
+install(TARGETS nglib ${NG_INSTALL_DIR})
+install(FILES nglib.h DESTINATION ${NG_INSTALL_DIR_INCLUDE}/include COMPONENT netgen_devel)
diff --git a/py_tutorials/CMakeLists.txt b/py_tutorials/CMakeLists.txt
index 895911a4..bf67b11a 100644
--- a/py_tutorials/CMakeLists.txt
+++ b/py_tutorials/CMakeLists.txt
@@ -1,5 +1,5 @@
 install( FILES 
         shaft.geo mesh.py exportNeutral.py
-        DESTINATION share/netgen/py_tutorials
+        DESTINATION ${NG_INSTALL_DIR_RES}/${NG_INSTALL_SUFFIX}/py_tutorials
         COMPONENT netgen_tutorial
        )
diff --git a/python/CMakeLists.txt b/python/CMakeLists.txt
index d35278f3..5f9c785a 100644
--- a/python/CMakeLists.txt
+++ b/python/CMakeLists.txt
@@ -1,5 +1,8 @@
-install(FILES __init__.py meshing.py csg.py geom2d.py stl.py gui.py
-        DESTINATION ${PYTHON_PACKAGES_INSTALL_DIR}/netgen
+configure_file(__init__.py ${CMAKE_CURRENT_BINARY_DIR}/__init__.py @ONLY)
+
+install(FILES
+        ${CMAKE_CURRENT_BINARY_DIR}/__init__.py
+        meshing.py csg.py geom2d.py stl.py gui.py
+        DESTINATION ${NG_INSTALL_DIR_PYTHON}/${NG_INSTALL_SUFFIX}
         COMPONENT netgen
         )
-
diff --git a/python/__init__.py b/python/__init__.py
index ca1e91bd..e74d1a49 100644
--- a/python/__init__.py
+++ b/python/__init__.py
@@ -1,19 +1,13 @@
 import os
-from sys import path
-from sys import platform as __platform
+import sys
 
-if __platform.startswith('linux'):
-    _netgen_bin_dir=os.path.realpath(os.path.join(os.path.dirname(__file__),'../../../../bin'))
-    _netgen_lib_dir=os.path.realpath(os.path.join(os.path.dirname(__file__),'../../../../lib'))
-if __platform.startswith('win'):
-    _netgen_bin_dir=os.path.realpath(os.path.join(os.path.dirname(__file__) + '/../../../bin'))
-    _netgen_lib_dir=_netgen_bin_dir
-if __platform.startswith('darwin'):
-    _netgen_bin_dir=os.path.realpath(os.path.join(os.path.dirname(__file__) + '/../../../../../MacOS'))
-    _netgen_lib_dir=_netgen_bin_dir
+_netgen_bin_dir=os.path.realpath(os.path.join(os.path.dirname(__file__),'..','@NETGEN_PYTHON_RPATH_BIN@'))
+_netgen_lib_dir=os.path.realpath(os.path.join(os.path.dirname(__file__),'..','@NETGEN_PYTHON_RPATH@'))
 
-path.append(_netgen_lib_dir)
-path.append(_netgen_bin_dir)
+if sys.platform.startswith('win'):
+    os.environ['PATH'] += ';'+os.path.realpath(os.path.join(os.path.dirname(__file__),'../../../bin'))
 
-import libngpy
-del path
+del sys
+del os
+
+from . import libngpy
diff --git a/python/csg.py b/python/csg.py
index f0e7823c..1e58f1bb 100644
--- a/python/csg.py
+++ b/python/csg.py
@@ -1,8 +1,7 @@
-import libngpy
-from libngpy._csg import *
-from libngpy._meshing import MeshingParameters
-from libngpy._meshing import Pnt
-from libngpy._meshing import Vec
+from netgen.libngpy._csg import *
+from netgen.libngpy._meshing import MeshingParameters
+from netgen.libngpy._meshing import Pnt
+from netgen.libngpy._meshing import Vec
 
 
 try:
diff --git a/python/geom2d.py b/python/geom2d.py
index bb5a12f6..47baa952 100644
--- a/python/geom2d.py
+++ b/python/geom2d.py
@@ -1,5 +1,5 @@
-from libngpy._geom2d import *
-from libngpy._meshing import *
+from netgen.libngpy._geom2d import *
+from netgen.libngpy._meshing import *
 
 tmp_generate_mesh = SplineGeometry.GenerateMesh
 
diff --git a/python/gui.py b/python/gui.py
index bf29a41e..fcd4872b 100644
--- a/python/gui.py
+++ b/python/gui.py
@@ -1,16 +1,15 @@
 import netgen
 
 def StartGUI():
-    import os
     from tkinter import Tk
 
-    from . import _netgen_lib_dir
-    from . import _netgen_bin_dir
-
     global win
     win = Tk()
-    dir_path = os.path.dirname(os.path.realpath(__file__))
-    win.tk.eval("source "+os.path.realpath(os.path.join(_netgen_bin_dir, 'ng.tcl')).replace('\\','/'))
+    win.tk.eval('lappend ::auto_path ' + netgen._netgen_lib_dir)
+    win.tk.eval('lappend ::auto_path ' + netgen._netgen_bin_dir)
+    # load with absolute path to avoid issues on MacOS
+    win.tk.eval('load '+netgen._netgen_lib_dir.replace('\\','/')+'/libgui[info sharedlibextension] gui')
+    win.tk.eval( netgen.libngpy._meshing._ngscript)
 
 if not netgen.libngpy._meshing._netgen_executable_started:
     StartGUI()
diff --git a/python/meshing.py b/python/meshing.py
index c9c8f511..f6ad65ce 100644
--- a/python/meshing.py
+++ b/python/meshing.py
@@ -1 +1 @@
-from libngpy._meshing import *
+from netgen.libngpy._meshing import *
diff --git a/python/stl.py b/python/stl.py
index 9ef75a57..032f2b69 100644
--- a/python/stl.py
+++ b/python/stl.py
@@ -1,6 +1,5 @@
-import libngpy
-from libngpy._stl import *
-from libngpy._meshing import MeshingParameters
+from netgen.libngpy._stl import *
+from netgen.libngpy._meshing import MeshingParameters
 
 
 def stl_meshing_func (geom, **args):
diff --git a/tests/docker_15.10 b/tests/docker_15.10
index a88f5673..b386f250 100644
--- a/tests/docker_15.10
+++ b/tests/docker_15.10
@@ -1,4 +1,4 @@
 FROM ubuntu:15.10
 MAINTAINER Matthias Hochsteger <matthias.hochsteger@tuwien.ac.at>
-RUN apt-get update && apt-get -y install python3 libpython3-dev libxmu-dev tk-dev tcl-dev cmake git g++ libglu1-mesa-dev ccache python3-pytest python3-numpy
+RUN apt-get update && apt-get -y install python3 libpython3-dev libxmu-dev tk-dev tcl-dev cmake git g++ libglu1-mesa-dev ccache python3-pytest python3-numpy python3-tk
 ADD . /root/src/netgen
diff --git a/tests/docker_16.04 b/tests/docker_16.04
index a1fe001e..2195714b 100644
--- a/tests/docker_16.04
+++ b/tests/docker_16.04
@@ -1,4 +1,4 @@
 FROM ubuntu:16.04
 MAINTAINER Matthias Hochsteger <matthias.hochsteger@tuwien.ac.at>
-RUN apt-get update && apt-get -y install python3 libpython3-dev libxmu-dev tk-dev tcl-dev cmake git g++ libglu1-mesa-dev ccache python3-pytest python3-numpy
+RUN apt-get update && apt-get -y install python3 libpython3-dev libxmu-dev tk-dev tcl-dev cmake git g++ libglu1-mesa-dev ccache python3-pytest python3-numpy python3-tk
 ADD . /root/src/netgen
diff --git a/tests/pytest/test_gui.py b/tests/pytest/test_gui.py
new file mode 100644
index 00000000..6e32488f
--- /dev/null
+++ b/tests/pytest/test_gui.py
@@ -0,0 +1,11 @@
+import netgen
+import pytest
+
+def test_gui():
+    try:
+        from tkinter import Tk
+        win = Tk()
+    except:
+        pytest.skip("can't create a window")
+    import netgen.gui
+
diff --git a/tutorials/CMakeLists.txt b/tutorials/CMakeLists.txt
index 0fea9d39..a2e70a6d 100644
--- a/tutorials/CMakeLists.txt
+++ b/tutorials/CMakeLists.txt
@@ -7,6 +7,6 @@ install( FILES
         twobricks.geo twocubes.geo twocyl.geo boundarycondition.geo			   
         hinge.stl  part1.stl frame.step  screw.step					   
         squarehole.in2d squarecircle.in2d square.in2d
-        DESTINATION share/netgen
+        DESTINATION ${NG_INSTALL_DIR_RES}/${NG_INSTALL_SUFFIX}
         COMPONENT netgen_tutorial
        )