I should mention GPO4 uses the modulation controller a lot. That means you really want a modulation wheel, not the stupid Roland return to zero modulation on their bender, and on my PC-180 midi keyboard controller. A Roland A-50 would be the ticket (which I developed 8^) but don't have! BUT JS: midi_CC_mapper does let me map the data slider defined as PAN to the modulation MOD wheel, you can also directly set the data slider to modulation, so all is good! Having used it a bit more, I must say GPO4 is brilliant! You do need more than a 4 octave midi keyboard, even with octave switching, or a split keyboard feature, to get to some of the keyswitch articulations of some instruments, if your actually playing everything. - Megacurve