Hi!

If You want to play a loop from the Techno board for example, just simply assign that patch to one of the parts. Enable the keyrange function and set it for only one key. Assign the piano patch You want to the next part and switch the keymode to layer at
Perform/common. I have a hold pedal and I use it for holding the loop. If You don`t want to hold the other sounds (in this case the piano) then switch the piano part and at Perform/edit/midi/rxswitch switch the hold function Off.

It works perfectly for me.

Regards: Tomi