There doesn't seem to be many options when you're trying to generate PDF (what an infernal format) with Tcl/Tk on Windows especially for scientific text.
Using a miktex backend
This seems crazy, there are so many files in the complete distribution, its insanity! But there seems to be a lot of useful LaTeX extensions (I've got a chemistry bent so it has to generate chemical text well)
What files are needed (what do I ship with) and how do I call those files to generate PDF? I'm going to start with LaTeX source, using chemistry extensions.
Using the canvas to generate Postscript then converting to PDF
This seems too low-level for chemical text.
Docbook backend
Is there chemical markup and win32 command line tools available for it?
A lot more research is needed... your help is more than welcome
So far the best way seems to be to go with the LaTeX backend and just decipher miktex