Can't load game after certain point

After killing the false baron, entering the room where Kythaela finds her spellbook makes all future saves corrupt. I have opened the door, can reload a save where the image on the wall has opened the door, but if I enter the room and watch the cutscene, the game won't load any future saves. The whole run is made on the same version, loading previous saves works fine, but progression is impossible if i cant load/have to do the rest of the game in one sitting.

Game version: 0.4.21