For all we know, the regs may be going into a Y harness and then to the receiver. I've actually seen this, and the guy doing it believed he had a redundant power supply to the RX.

I suspected a misunderstanding when I read the header "redundant Rx" setup problem.

Until you actually SEE a set-up, sometimes it's hard to tell what is really going on.

Yepe, given the problem you have described and the overheating Fromeco, it would be much safer just to use the one Powerbox digiswitch and a single 800-mAh battery, which is a common set-up with many experienced Pattern fliers. Move the control surfaces around (while on the ground!) to check for binding and to see if the Digiswitch reg heats up.

I wish one of us could be there to inspect the whole set-up in person, but since that isn't possible try to find somebody locally who is experienced with good Pattern set-ups. In any event, I wouldn't risk flying a nice model until I got the issue resolved.