The jetways are handled entirely by FSX. We just provide the bones that controls the model, but the model it's the same, regardless were it's placed.
Sometimes FSX just can't handle the animation very well on certain airplanes (yes, the CRJ seems to be affected more), the wheels usually have issues, and this is happening with the default jetways at defeault airports as well, on some airplanes.
There's not much we can do right now, other than replacing the FSX jetway system entirely with something we can control better, and this is already under consideration.