BlitSnd
Documentation and code of BlitSnd routine + tools are available here
Workflow overview
BLSConvert
Converts XM or MOD (following strong constraints) into BLS or BLZ format
BLSPlay
Player on PC / STe playing BLS or BLZ format (STe ASM version only plays BLZ)
SynthYM
YM sound player to help designing YM sounds set
BlitSTracker
Specific hacky Milkytracker fork for BlitSnd routine (4 PCM + 3 YM voices)