After some debugging -using the info I mentioned the other day- some game that used to crash "randomly", I've found that all the crashes I could reproduce were related to Tremor (the library used to play OGG files) and in particular to oggpack_readinit. I believe this problem arises more on games with multiple sound sources playing at once, and doesn't seem to appear in simpler games with only one or two sound channels.
This error might well be related to this other bug or even this other one.
I'm not really sure I'll be able to fix this anytime soon, but I've made some simple tests with MP3 playback and they seem to work much better; the interpreter doesn't seem to crash anymore and I believe that both bugs mentioned above might also go away. If this is true, I'll update the transcode_music scripts so that they recode&resample your music to MP3 by default.
Just one note: You will only be able to play what smpeg can: MPEG-1 - Layer III sound files (the simplest/oldest kind of MP3 available), but hopefully the transcoding script will do all the hard work converting your files so that you don't have to.
Hope this solves stability problems, in case you found'em.
Happy coding! :)