Load Error Code 800/801

It seems that one of my saves is corrupted, but only Willow Creek is affected. I only noticed it on 2nd of February, but I think it happend a while ago. I have a version of this save file from July 2025, which works fine.

I had 3 residential rental lots in Willow Creek: Daisy Hovel, Garden Essence and Bargain Bend.
When I tried to load to build mode in one of the lots in this neighboorhoods, through manage worlds, the lot was empty in build mode and the lots around showed the default builds. But, when going back to manage worlds, there still was the preview of the lots I placed.

In live mode it wasn't possible to travel to or move to Willow Creek at all. Either I got the error code 800 or I was stuck in an endless loading screen.

I have following mods installed: 

-McCmdCenter_AllModules_2026_1_1
- MCWoohoo_ScriptAndPackage_2026_1_1
- TwistedMexi's Better BuildBuy v4.3
- TwistedMexi's TOOL v3.1
- UI_Cheats_Extension_v1.52
- [ellcrze] simple cas room
- More_CAS_Columns_(4_Columns)
- Tmex-AlwaysFullEditMode
- Tmex-AlwaysTesting
- TURBODRIVER_FixSocialBunnySimulationLag

I would provide my save file if necessary.