From what I know, the music and sound comes from the cd. If you can get the music onto the cd, then it might work, but only if you replace one of the existing music files.
(eddie quietly creeps through the door hoping cam doesn't catch him with a stupid answer...)
Easy, kinda, well, the way that I "sorta" did this in Anstieg was to just stick a "play sound" event with the song or speech that I wanted at various points.
You can have it be for"every turn" if you want, and then it is like background music.