Check sounds.ini at the end. There is space for up to 10 tracks. Blank ones will not play, but it will play tracks 1-10 in sequence, ignoring blanks then restart at 1. Only battlesounds 1 and 2 are on the play list ATM.
Don't use too large files (they take up lots of memory), but the DirectShow interface should handle any legit music file you have - WAV and MP3 have been tried.
The only problem with MP3 (and why we have replaced all with WAV) is that some users install third-party applications that override the default Microsoft DirectShow MP3 Codecs with their own, and that seems to sometimes mess with the DirectShow sound MP3 playback. WAV files do not have the Codec compatibility problem.
I'll go back and see if I can trim the files as they are big wav files (56,015KB, 101,539KB and 105,317KB).
Now that I know how it works I might go back and see if I can put 10 files together that sound okay. Hmmm, maybe a Celtic collection so I can throw in some pipes and drums...
I think Andy's right when he says he doesn't waste CPU's on music or sound. I've got a 10 year old system and while I've upgraded the cpu and maxxed out the memory it still struggles at times. I checked out the vuplayer and I think it's neat but the music still skips or becomes choppy on occasion. For now I'll go easy on the music and look into getting into the 21st century with an IPOD or something along those lines.