Ah nice, were there more games that didn't support the old bms to midi website method? I know LM was one, didn't know pikmin conversion never worked either.
The PHP script was always buggy, I could never get it to work with any game. So I made a C script. The advantage of mine is that it only uses <stdio.h>, so is platform independent.
You mean the instruments? Those are not in the BMS file at all, they're in separate AW files. It's easy enough to extract the waves, but the note mapping, ADSR envelopes and the like are not documented.