Had guests staying for a few days plus I need to do a bit of work updating my xAP UID's based on the Cortex changes so I haven't been playing with Cortex in the last few days too much. I noticed one issue in the previous update (that expanded the sub addresses) where source addresses had a '.' appended but I believe Vivian fixed that really fast. It would cause the issue you mentioned though as control uses the source address identifier.
xAP Viewer is a very good tool to ascertain if the issue lies with Cortex or xAPFlash. I'll be running with the updated Cortex in the couple of days and I'll let you know if I find anything similar...
K