As the topic states, whenever I enter an "interior cell" of some kind, the game crashes to the desktop with an "divinity 2 has encountered an error..." message.

I had the initial perpetual load screen error, which I bypassed by using a save game file posted on the forum.

I was able to do the Fanglow tutorial part, but in Broken Valley I can't enter the barracks, or any other buildings around the map.

I couldn't find anything about this particular problem on the forum, any help would be greatly appreciated!

I'm unsure what info about my rig could help you, I have an AMD 3500+ with 1,5 GB of ram, a Nvidia GeForce 6600 GT (yes it's old, but it works :P ) with the latest drivers, and Windows XP.