limitedvaeh When you say the problem isn't your mods, does that mean you've tested with your entire Mods folder removed? If not, please do that just to be thorough. I don't want to waste a lot of your time testing other potential causes if this would fix it. And I'm not suggesting you play without mods or cc in general, only that something else could be broken that didn't cause an issue before now.
If the game does the same thing with your Mods folder removed, please test a different lot in one of your existing saves, one on which you haven't built before and that doesn't have any Gallery content on it. If that lot is affected too, please test a new save, again without downloading anything from the Gallery.
Just tried without my mods folder and it did the same thing. Also the flashing thing stopped when I put my game into windowed fullscreen mode but it still freezes when trying to go into build mode in the save file even without my mods.
