Just a warning, I had the PC demo installed before purchasing the game on Steam. After playing the full version for a while I uninstalled the demo. Unfortunately this deleted the Users\USER\AppData\Local\Divinity 2 folder without any warning. This folder holds the savegames for both the demo and full game so all saves from both are lost.
It seems the demo should use its own folder for storage and even then the uninstaller should prompt for confirmation before deleting the user data.