Err, I don't think a single thing was correct in that post.
Technically you don't even need my driver to make the game work in WINE, that just makes it easier for you.
WINE supports MANY DirectX features, among them Direct3D and DirectShow.
And that brings us to the last point, my driver completely replaces the movie player with one that only needs DirectSound to work, it never touches DirectShow. (And DirectSound is of course supported by WINE)
Now to answer some of the original questions; WINE has it's own regedit program, functionally equivalent to the windows version, simply run that on the .reg file to import it. FF7Music works fine as long as you enable the WINE-specific plugin in the config.