Korg NanoPad2 - Cutoff effect on touch pad with GarageBand

I recently got a Korg NanoPad 2 for use with GarageBand, but I have no idea how to map the Filter cutoff of the radio sounds instrument to the X-Y touch pad on the side. Any ideas on how to get it to work?

EDIT: Also, I use Korg Kontrol Editor to map out keys and that