Were you able to load these saves previously, or did they crash the first time you tried?

If you have a save at the end of act 3, can you reload it, enter the academy, skip the cutscene, save the game right away and load that save?

In Windows Explorer, browse to the '..\Beyond Divinity\savegames' folder, and check the number of files in the act 4 save game folders. Before entering the battlefield in my act 4 saves there were 23 files in the folder, while afterwards there were 29 or (less often) 30.