It doesn't like any of my Pokemon games. It crashes when trying to play files, and it doesn't like scanning for the soundtable in FireRed BPRE.
If you're wondering about Sappy 2006 Mod15 not showing the tracks in FireRed, well here's the interesting part. Sappy doesn't need an .xml file to be able to play and read the tracks in the ROM, you can just change and type in a higher number for which song you want to edit or play. In FireRed, the sound effects go from 1-255, while the BGM goes from 256-346, remember... the song number is in decimal, not hexadecimal.
Try typing in 298, then press play, and you'll hear the Kanto wild Pokémon battle music.
Maybe we'll have to see who is actually good at making a .xml file so that anyone can choose the song they desire, or you can always import the .xml from the normal Sappy 2006 (the buggy one of course). But I think it's best if someone creates a better .xml list for song list from what Kawa listed, like SE01, BGM01 and so on, because anyone is bound to insert new songs into their ROM Hack.
Oh and on another note, Sappy will only freeze if you select a song number that is blank and empty (that's right, free space!). So here's what you do, don't click play after when you put in a number higher than 346, instead... just click anywhere on the main amplifier area on Sappy and it will act like nothing happened. And you can insert new songs into the blank and empty spots.