Please email supportdos@larian.com, with a description of the problem and the report.zip file generated by the
D:OS support tool (for the PC version). The report will contain system and game information, any crash dumps, and your saved games. If file size is an issue, any saves not related to the problem can be deleted.
If the problem reoccurs, you could try browsing to the '..\Documents\Larian Studios' folder and renaming the 'Divinity Original Sin' subfolder.
This folder contains the saved games, configuration files and a level cache folder. Deleting or renaming it will get the game to recreate it on startup; playing the game from a different Windows user account would effectively do the same thing.
If the problem is in the level cache file for Hiberheim, then just moving your save folders from the old profile to the mew one may solve it (wouldn't help if the problem is with the game itself, or the saves).