chrashing when using vst3 and playback problems

In Musescore 4.3.2 using HALion Sonic (or Kontact, or any 3rd party vst3 instrument) there is no sound when playing the score. MSBasic works fine. Sometimes after playing the score with MSBasic the VST3s output sound. If I save a score with the third party VST3 selected, then try to open Edit + Preferences it immediately closes the score w/o warning, or Musecore hangs.

In Aug7 2024 nightly (MuseScoreNightly-242200305-master-f2046a0-x86_64) I get sound from the VST3 (HALion Sonic). But if I save the score and open it, or just got to Edit Preferences it hangs musescore. Has to be terminated.

Here's a file: it loads fine. But if you select Edit + Preferences is either hangs or crashes.

VST3s all work fine standalone or in Studio One, REAPER etc.
Windows 10, SSD, 16Gig RAM, IK Multimedia AXE ASIO.