PEC and GPG are 2 different things, and up to now, EqMod can not handle the PEC feature, but Hy Murveit is currently developing the support for Eqmod. I was involved in but I had to give up when I found out my old HEQ5 pro cannot support PEC (it's one of the 1st version). But you might help for dev if you want.
Look at
this thread
, it might be helpful to understand GPG behavior. The
documentation
should be up to dtae too.
@Hades, I'm pretty sure EqMod driver knows the RA worm position, it should be in motor control tab, Stepper position.