pb1866: I'm betting it's related to the fact that scummvm lists this game as 10% compatability... most notably the fact that the music isn't working. Probably once this issue is worked out the game will be released.
Waxworks is listed as 10% supported under ScummVM, since no one has actually confirmed it is completable under ScummVM.
Unfortunately the music format used by Waxworks (DOS version) isn't documented anywhere, and currently disabled under ScummVM due to been unstable.
Bicro: The game does have an ancient form of copy protection (password) ...gonna be interesting to see how they dealt with that.
GoG have been provided with updated executable file, with the copy protection disabled, so that shouldn't be an issue.