Doesn't load world since new update

I started a new world very recently, and since the update I can't open my world that I created. I can still play with the same character I created, and I can also play on other worlds. The world was not yet on the cloud, but my local tmodloader folder clearly has the world back-up from yesterday (+ some other backups from previous days). I literally see them. Still it gives me the error message I added on screen. Just as an added bonus (I don't think it is the problem but I'll add it just in case), when I start up regular terraria I get this error message about resource packs. Maybe that also gives a clue to the problem, probably not.