There are several remaining issues which prevent MSV8 from actually running (something I didn't test).
- The debug build was linking against the release Python static library. This does not work and PyInitialize is not called resulting in the GUIScript module initialisation failing fatally.
- Python binary releases are compiled with VS7 and will be for the indefinite future. This is a problem because the reason this is done is because there are problems with embedding and extending between Python builds compiled with VS7 and other versions. I removed all the Python installation paths for libs and includes for all the different installation versions and now it expects a 'MSVC8/GemRB/python' source directory, which is expected to have been compiled separately with VS8 of course.