Hi! Copying all CD's to hard drive works great after I figured out that you need to edit CD.DAT to reflect the CD number appropriate for where you are in the game. Otherwise missions are not available.Thanks for the comments!
Quarto: gameplay tweaks are definitely a possibility, although i'll probably prioritize fixes related to game stability. I'm with you on the endless respawn waves though.. I can't say i encounter them often, but when I do, yeah they can be annoying.
Oceankhayne: thanks for the feedback, that's definitely useful to know. Admittedly, we didn't test the patch with third-party MIDI synths, but i'll try to reproduce the issue sometime within the next few days and see if a work-around can be found (no promises at this point, though).
Riddler / AD: just copying the files without installing should be fine. I don't think the game has any registry dependencies (besides, just unzipping the patch into the GOG release seems to work, and it is based on the DOS version)
edit: don't forget to edit DARK.FIX if you copy the game files into a drive other than C: