Midi-Out problem

Hi erverybody! I hope anyone can help me.
I play a Hughes & Kettner Trilogy and the georgous G-Sharp (unfortunatly not continued!!!)
My footcontroller is a Engl Z-12. All devices sendIreceive on MC 1. It works when I send a PG to the Trilogy and it even works when I send a PG to the G-sharp. But connected (Z-12 into Midi in of the G-sharp - from the midi out to the midi in of the Trilogy) the PG seems to stop in the G-sharp. Did I forget to programme something in the richt way . there's nothing to find in the manual. PLEASE HELP!!!

Some helpless, hopeless and desperate german dude ;-)