I just downloaded and installed latest 2.3.13 and it fixed my issue. I am not sure why I didn’t try this version earlier. It looks like my issue was different than Kevin’s.
With focuser’s driver backlash compensation disabled and SGP’s backlash compensation enabled, I finally can send focuser’s new position to the focuser without SGP focuser’s locking up or stop communicating with the focuser. I can physically see the motor overshoot and then reverse direction to the proper focuser’s position. It never happened in previous two revisions.
Next test will be auto focus run. Hopefully the weather will clear up this weekend. If the auto focus run is unsuccessful, I will try SGP version 2.3.5. I still have focuser’s ASCOM driver backlash compensation that works well in case SGP 2.3.13 auto focus run with SGP’s backlash compensation enabled does not work.
Kevin, using SGP latest 2.3.13, have you tried a simple test like sending new focuser’s position and see if the motor overshoots and reverse direction to correct position?