Yeah I'm having the same problem, I thought at first that I broke my world and I was freaking out (+200h worth of map building) but then I realised that in the "One World" workshop itself it bugged as well so I tried uninstalling everything and reinstalling and nothing changed, I unsubscribed and resubscribed but nothing neither. So I was looking all over the internet until I found this. Glad to see I'm not the only one. Like I can load the "One-World" and the background pictures but I can't build anything.

im having sporadic issues; built one map post update no issues, builds everytime. another map ive rebuilt twice and upon exporting and importing, wont build at all. it loads the screen image but thats it.