I think I know the issue that you are having with your graphics card. I had an issue that seriously isn't documented anywhere, but it works.
After installing and modding the installation, try and launch "FF7Config.exe" from your FF7 installation folder.
If it doesn't open, then you most likely have the same issue that I had.
1. If you have an NVidia card go to the directory "C:\Program Files (x86)\NVIDIA Corporation\coprocmanager" (It may be different directory on your system).
2. Rename the file "Nvd3d9wrap.dll" to something else.
3. Afterwards re-run the FF7Config.exe. If it works, set your display device, sound device, etc.
4. After closing FF7Config, rename "Nvd3d9wrap.dll" back to the original filename.
Then it should work. I hope this helps.