Sprite glitching in 2.5+, frame change crash after 289.3 from physics engine

I haven't updated in a while because of a crash upon changing frames after build 289.3, but with 2.5+ I decided it was time.
After some investigating I found that if I UNCHECK "Insert nonphysical objects in the world" on the Physics Engine, it would no longer crash upon changing frames, horay!

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But now after changing frames, it seems there is sprite glitching/swapping frames of animation between separate objects...

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I'm wondering if this is due to something in 2.5+, or, if I had unchecked that box on the physics engine, would it have done this sprite glitching in the build immediately following 289.3? Either way, it's happening in 2.5+ currently, so hopefully there is a solution..

(The second image was supposed to come through as a gif, to show glitching in motion, but you can see a second armless orange guy near the rock on the right, that's actually supposed to be a sparkle, not a player sprite).

I think sending PMs to staff is disabled...

I have some weird information. A friend suggested it's not the physics engine but a memory problem underneath. So I re-enabled that Physics Engine checkbox, and started deleting other things one at a time until one object was in particular was causing the crash. I removed a qualifier from that object and it didn't crash. So then I went to the code of that qualifier and I disabled a specific event, and in doing so it stopped crashing immediately, but would still crash after changing frames a couple times! This was all on a very old version of the project, and on my newest version, removing the qualifier code hasn't fix the sprite glitching..

Please login to see this attachment. but I went to make a new message and manually typed 'Yves' into the recipient field. Hoping it worked.

My most recent MFA is 31.5 MB, I don't know if this is too large to send here.