Could he load the character before the patch was installed?
Does he have any older saves he could try? It sounds like your own saves as OK.
Check the number of files in the saved game folder (in '..\Divine Divinity\Run\savegames'). Missing files might cause the game to crash when trying to load. A new game should have 22 files, after going to either Verdistis or the Dark Forest it should have 27, after going to both it should have 32, and after getting to the wastelands it should have 37.
