Hi JIm,
what kind of porpoising did you see? What were the conditions? Real weather, speeds, weight, CG? If you could post a picture (or a series) of the instrument panel of when it happens, that would be great, a video would be even better!.
We had to retune the PID values for most of the autopilot and there may be some fringe cases when the dampening doesnt work as it should, so I would be very interested to understand (and fix) your problem.
Cheers, Jan