11/3 Update - Possible related issue? This time I’m getting error messages upon saving but no freeze. Major - "Asset failed to save" error - "Asset does not have any of the provided object flags"
11/2 Update - Problem fixed!
As of the 22.35 update I’m no longer experiencing this problem. Thanks, Epic! 
10/23 - Update
Today I was creating some new material graphs in UEFN and the program crashed, with a proper crash report popup, not just a freeze. When I reopened UEFN all of the box meshes I had created in the scene to test my materials were gone from the viewport, outliner, and content browser. My materials were saved, thank god!!! The meshes had been in the scene for probably at least an hour, so I think Autosave and manual save are broken. I can’t remember how frequently I manually saved - probably not often since I didn’t trigger a freeze. The meshes that were deleted were boxes and cylinders I generated with the modeling tools.
This is a serious blocker for me, to the point where I’ve now officially decided to start creating my environment in Unreal instead of UEFN, and then I’ll export it over to UEFN when I feel like it’s safe to use UEFN without losing my work. The UEFN modeling tools are broken, so I model in Unreal already. I don’t use terrain and I don’t use FN meshes, so I don’t need to worry about those. Unfortunately when I export models between Unreal and UEFN my polygroups are lost, and materials aren’t compatible so I have to recreate all of my material graphs from scratch. I also can’t test FN mechanics like my Verse scripts in Unreal, but Building Props have been broken for me for nearly a month (see these Forum links) so it’s been impossible for me to create many of my mechanics in UEFN anyway. Blocker - Building Props intermittently broken - don't take damage , Blocker - Can't test building props for the past month - Infinite Downloading - #21
It’ll be an interesting experiment to test the Unreal to UEFN pipeline though, so that could be a bright side.
Logs:
BlueClairy_Logs_Oct22.zip (246.2 KB)
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10/22 - Original Post
Today and yesterday UEFN has been intermittently freezing for me when I try to save with Ctrl S or by clicking Save in the menu. When it freezes I can’t click on anything, and I need to force quit through Task Manager on my PC. Sometimes saving works, but most of the time saving triggers a freeze.
When I reopen UEFN much of my recent progress is lost, because anything I was trying to save at the time when UEFN froze didn’t save. I also suspect AutoSave might not be functioning well, because when I reopen UEFN way more progress is lost than I would have expected. Maybe my environment only saves when I manually save it (if manual save works at the time). Sometimes it seems like even changes that I manually saved don’t appear when I reopen UEFN.
Currently what I’m working on is art, not mechanics. So, adding, deleting, moving, and manipulating meshes, and editing materials. I’m not using terrain, everything is meshes. All of my meshes are either modeled by me in UEFN or modeled in Unreal and imported into UEFN, so no FN meshes.
Not sure if this is related, but yesterday I also noticed that a static mesh model I had been texturing became invisible after I left UEFN and returned, even though it still showed in the outliner. I couldn’t get the mesh back.
I don’t want to keep losing my work, and restarting UEFN takes time, so I might switch over to creating my environment in Unreal and export it over to UEFN when I’m ready to add FN mechanics. I’ve already switched over to Unreal for modeling and texturing because the UEFN modeling tools are broken.
Here are my logs, if it helps! Thanks!
BlueClairy_Logs_Oct22.zip (246.2 KB)
Process Explorer won’t allow me to.
It’s tricky using software that’s still in Alpha, because there are always gonna be bugs to deal with while the product is still being developed. Exciting but sometimes frustrating. Us creators are all in the same boat, in that way.