Any sustain pedal with a 6,3mm jack that closes the contact when being pressed should work. Our recommendation is a Fatar/Studiologic VFP1/10. Only use a single pedal, dual pedals won't work.
The pedal should be plugged in before the device is turned on. While the device is switched on and during booting, the pedal should not be pressed, otherwise its state will be inverted.
For the swell / continuous pedal, we recommend using a Fatar/Studiologic VP/27. Otherwise, other 10k maximum resistance expression/swell pedals with linear scale should work, too.
For both sustain and continuous, pedals compatible with Fatar, Roland, Moog, Kurzweil, M-Audio should be working as well.
The Korg/Yamaha models may not work though.