Nice work remembering how to do the MyST conversion. FYI, WTSS was already ripped in MYST_Data_4.lha under MISC.

Did Phil need the ym.wtss file at all? He's running the ST game code (patched) so presumably he could find the original ST play routine in the code and then redirect writes to the YM register addresses to the MyST emulator's data buffer?

Speaking of which I don't suppose you know how to use the YM2149.bin included in the main MyST archive? There are no examples of how to use it in your Amiga programs.

I've emailed Nicholas but no reply yet.