[Zubersoft]

Go through the manual for the organ and figure out which messages it needs to receive to switch presets. Simple instrument changes can be achieved by sending a patch select message usually.  If you have more complex presets, you will need to determine what messages the organ requires to switch those. MobileSheetsPro now supports MIDI over bluetooth, so you'll have to either connect your tablet to the organ using USB or bluetooth (if the organ supports MIDI over bluetooth).

Mike