You're not the first to ask that question, more like the 100th ..
Savegame compatibility is not supported for different versions of the beta/early access. The main reason is that any bug report that is uploaded to the developers would not contain a bug that is caused by savegame incompatibility (they don't have time to account for that).
Once the game is fully released, your savegames will remain compatible with patches released later on. Until then, if you don't want to restart a game with every update, disable auto-update for Divinity Original Sin.
I work too many hours and spend WAY too much time rerolling chests for good loot.