RE: Vectored thrust set up on 18mz
You can do a few simple mixes: Elevator->Nozzle-1, Elevator->Nozzle-2, Aileron->Nozzle-1, and Aileron->Nozzle-2. You can assign them a single switch to turn the mixes on and off, or have them active within a condition. Since you have two servos assigned for each nozzle, you don't need separate mixes for them.