Need help with MIDI on OctaMED Sound Studio

[Zadoc]

Right click menu, select "Block" and "Set Properties" (or Right-Amiga-B) to get to the block properties and adjust the slider for however many tracks you need.

[Zadoc]

Yes, clicking the Instrument "Props..." button will also let you change MIDI channels and presets.  Just out of curiosity, if you're triggering your drum sounds via MIDI (I'm assuming a drum machine or rack synth) why would you need each individual drum on a different instrument?