It sounds like one of the files in the save is corrupt. Do you have any recent saves that work?
Try saving under a new name, or make a copy of your saved game folder, then delete the 'world.x1' file from that folder (in '
..\Divine Divinity\Run\savegames'), re-load and try Verdistis again. This should this fix the save problem, though will result in items directly on the ground being lost and quest opened locations being resealed. Work arounds for this are described in
Game crash upon going to Verdistisand
Game crashes when I try to return to Verdistis.