Larian Studios Forums Divinity - Original Sin Divinity - Original Sin - General [bug] NPC Trading Crashes Game

I, too, am having this same issue.

Do you happen to have a lot of items in your inventory? I've spent the last 6 hours or so in-game robbing Cyseal blind of everything that isn't nailed down, and have accumulated a lot of stuff. It didn't seem to crash when I had very few items at the start of the game, even if I'd sit in the trade screen for a long time, but now I have the same problem you are having - at least I think. If you double-click an item from the trade window to put it back into your inventory (or to put it back into the NPC's inventory), the game will crash. However, if you drag the item back to your inventory, it is OK.

Hope the devs resolve this issue soon.