dtaipala,
Are you sure AHP is actually talking to the CM15A?
From your excellent symptom description, I think the CM15A is 75% good. It receives RF, transmits PLC, updates activity monitor, etc. CM15A is talking to AHP but AHP isn't talking back.
Moving the CM15A shouldn't cause failure, so did you by chance change USB cables in the computer swap? Check the connectors at both ends. Does another USB device plugged into same USB port work OK on new computer? etc. etc.
Also I vaguely remember Jeff Volp commenting on the split reactive power supply in the XPCR and problems that could occur if one of the legs is lost (i.e your use of the XPCR from 120V outlet). If Jeff reads this perhaps he will weigh in.
Jeff weighed in and I was thinking of something else. Disregard the preceding paragraph.