My experience pretty much follows that of Peter.
Paramount MX+ purchased in 2021.
Multiple attempts over multiple nights, using both the Legacy Method and the new TrainPEC Method.
Result: 100% failure.
After I installed PEMPro, I had 100% success from Run 1 and subsequent runs as I investigated the issue.
I set up and tear down every session.
With PEC trained via PEMPro, a 100 Point T-Point Model, Accurate PA and ProTack enabled I have no issues with unguided 60 sec exposures at focal lengths of 2350mm (C9.25 F10) and 2415mm (Mewlon 210 F11.5).
Dennis.