It seems I've found a flaw in the interaction between the Profiler and RM.
I had about 1350 rigs on my Profiler. scanning it from RM only 1000 were detected.
I then started deleting hundreds of rigs installed in the Profiler in sequence in several steps from the RM.
Even when the overall number of rigs was way below 1000 there was an inconsistency between the number of installed rigs reported on RM and that reported on the Profiler.
I had to restart the app in order to realign the two data.
It seems that while the Profiler was actually deleting rigs, it did not rescan its own database or it did not communicate with RM: the number of rigs reported by RM was (incorrectly) 1000- deleted rigs, that is a smaller number than the actual one.