That Torpor light is awfully similar to the Gruso one. Must speak to my agent about that. I've replied to this over on the OP boards: http://boards.openpandora.org/index.php?/topic/5322-how-do-i-enable-a-usb-midi-cable/
I can also help out with some pre-configured Hatari stuff, just contact me directly.
MIDI seems a bit stuttery in Hatari so I don't know if it's ideal for any serious work... still fun to toy with though.