but I can't see why it shouldn't work in principle.
Implementation wise, what differs from Togl 1.5 is that Togl_MakeWindowExist()
is replaced by Togl_CreateWindow(), a function that gets registered in Tk as a callback for window creation. In Tk/Tk 8.4a3, there is a new public API call
Tk_SetClassProcs() to register this callback, but for earlier versions of Tk
one needs to do this using some pointer magic.
There is a run-time check to determine which method to use, hence the
same binary runs on all versions of Wish from 8.1 and up. For this to
work you need to compile against the headers from Tcl/Tk 8.4a3 or later, or
the binary will only work for Tcl/Tk 8.1-8.4a2.
The tk8.4a3 public headers (tk8.4a3.h + tkDecls.h) are included for