Oscar
The whole point of this PP is that it uses the
change in Z heights to generate the M3 and M5's .
Even if you have not got a Z Axis connected you need to leave them in.
From the Doc's
Important! For the start and end cut states to work correctly, the machining operation must specify a target depth that is below its stock surface value. It is the action of the Z move going below stock surface that triggers the start cut event. To prevent having to remember to set these parameters for each machining operation, default stock surface and target depth values are set in the plasma CAM style library.
Dave