Don't spend any more time on this. AP has just responded and indicated that they have found a bug in APCC which causes the RA Rate coming in via ASCOM to be inverted. This happens only when APCC's Tracking Rate Correction feature is enabled. Your last post also caused them to look at high CPU usage and they found some old code that is probably responsible for that. I had passed your last message to them verbatim. Stay tuned for an update from AP pending their QA tests under live skies.