Problem with Quick Controller

I have a problem with the Quick Controller of Cantabile Solo 4.0:
When I choose the OnScreen Keyboard, I am able to change the CC64 (Sustain Pedal) with the “Toggle”-Command via Quick Controller. When I use my Korg microKey USB Keyboard, I cannot change any CCs (the Midi Monitor shows no CC-changes). I tried to supress all CC-Events from the device with the Midi Filters and I was looking for any option, that prevents the use of the QC. Unfortunatelly I haven’t found something.
But when I toggle the CC64 to “On” on the OnScreen-Keyboard, this value sometimes remains, when I change the Midi Input for the instrument.
Did I miss something?