Layout suddenly will not load - not even on old backup files

Hey all, first time poster. I've encountered a very strange problem with the game I'm working on. All of a sudden, one of my layouts will not load. Period. I haven't done anything to this particular layout or its corresponding event sheet in probably months, and today it just decided it wasn't going to load. Every other layout works perfectly fine, including other layouts that use the broken layout's event sheet.

A few things I've tried, but with no luck:

-Updated video drivers

-Changed settings in engine to lower performance

-Tried running the game on a different computer, same issue

-Tried opening an old backup file I have of the game, and the same layout is broken on that one, too!

By "broken" I mean it simply will not load. When running debugger it loads a handful of assets but the screen stays blank, there's 0% CPU usage, nothin'.

Here's a link to the cp3 file, the layout in question is "Lake Somnia":

drive.google.com/file/d/1f0jVjr7pNrO1EAkfTHLkbrQ9cWN69hZw/view

Any help would be greatly appreciated, thanks in advance!!

Update: I think I might have figured out what the problem is, I will make some changes to the event sheet and let y'all know!

UPDATE 2: Okay yeah I jumped the gun on writing this post, turns out I had an old 3rd party addon that was no longer compatible with the latest version of C3. I replaced the addon with an official one, uninstalled the 3rd party addon, and now it works perfectly fine.

The lesson I learned from this is, always check your third-party add-ons when C3 updates!