During assembly, it seems like you need to have a calibration routine to set the servos to their midpoint. Would you do this by replacing TestRun() in OpenCatEsp32.ino with servoTeamMiddlePoint()?

Another quick question: what is the scheme for connecting the servos to the BiBoard? Roughly the same as the Nyboard?

I'll give that a try. The odd thing is that module test programs all work fine, only OpenCat gave me problems. The Bluetooth adapter works perfectly, however, so I don't have any urgency for now.

That's awesome, thank you! That looks like enough to get started with.

It might have been an issue with the USB programmer. The Bluetooth interface worked fine. All good. It balances and recovers well, so servos etc are all working correctly.