From the support page:
How do I go Bank Down?
There are a few different ways to go down through Banks in Bank Mode:
-Press Bank Up (Right Footswitch) and then turn the Encoder knob counter-clockwise.
-Assign an Aux Switch to Bank Down.
-You can go Bank Down via MIDI CC. This can be set up in the RCV CTL menu in System Mode/MIDI.
Although, I have used the Disaster Area MIDI and it's great! You've got to love being able to jump from preset ONE to preset 99 with one push of a button.