I had reverted my FO4 after the recent auto update broke it, but then when I heard F4SE was updated, I updated that, updated FO4, then updated Sim Settlements and Unofficial FO4 patch, as they all presented new updated. Then I couldn't build. I messed around with disabling various things, and finally I had Vortex uninstall all mods, and loaded up a save. Suddenly I could build again. (Plus, Red Rocket elements I had scrapped were back in place.) Edit: I'm still able to build with mods installed but disabled, and launching via F4SE. Reenabling mods returns the building problem. I've got 80+ mods installed. I don't really want to enable and check one by one. . .