Considering the problem with Rim of Magic and Pawnmorpher, a simple way to mend it, at least for now, while a proper fix can't be implemented (If ever) i trait that makes a pawn, un-morphable.
It would prevent the trigger of mutation and the addition of Aspects, that seems to be what breaks RoM to work.

Evidence. One of my main colonist, a scientist with a RoM class was all well, even when he started to mutate. Bellowing lungs, some fur. No problems with RoM.
But as soon as he go an Aspect "Pack Minded" his RoM reseted to 0.
If a trait could be added, that makes a pawn immune to mutations, would bring some compatibility.


Also, with this i think it's safe to point out that the problem for integration would be, possibly is on the Aspects part of the mod.
It's an amazing mod. Both are, so some ways to make them compatible are pretty cool.