For info, in TSX they have made a change in the latest daily build.
"For Paramounts, implement 'Sync mount into existing model' as an single, instant operation. In the two prior builds, 10031 and 10133, 'Sync mount into existing model' was (temporarily) implemented as a TPoint recal which caused some confusion - when using these builds to 'Sync mount into existing model', upon Sync, press OK to the 'Start Calibration Run', and after the pointing sample is added, the cross hairs will jump to the sync star and the 'Sync mount into existing model' operation is complete"_
I have asked them to confirm if that is also implemented through ASCOM too, as was debated a few months ago.