DS> > Hello, same problem here with my VM under headless Ubuntu server. 
 DS> > Here only Py3 ai used but same error, i don't know how to solve, do you 
 DS> > news? 
 DS> 
 DS> No, I've not found a solution. I reinstalled everything from the OS up
 DS> and only installed Python 3.9 and I still get the error:
 DS> EAccessViolation Access violation

Their problem does not appear to be the same issue, just off the little knowledge I have.  Their setup sounds like an environment issue and yours I don't think is.

Since your script is running and throwing an access issue when closing, its more likely to be a bug.  As you may or may not know,
the current version for 64-bit ARM is the first release of it, so that makes it even more likely to be an issue with Mystic.  I can only assume when you say latest Pi OS that means you're using 64-bit OS and Mystic 64-bit for ARM.

The reason I hadn't responded yet is because I haven't had time to get my 64-bit Pi out to see if I can reproduce the issue on my own.

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--- Mystic BBS v1.12 A49 2023/01/31 (Windows/64)