Hi,
I purchased the Steam version of Divinity II yesterday as part of the Humble Bundle, and have since been struggling to find a fix for this problem (I believe it's the same as in
this thread, for more details read below).
This will sound strange, but I simply can't turn my character/pan the camera if I move my mouse too quickly. In other words, I can play normally as long as I drag the mouse very slowly on the mat (reducing DPI and mouse sensitivity helps), but as soon as I exceed a certain speed the camera locks in place. I can then run the mouse all over place, but the view won't turn at all, until I start moving slowly again. It's very frustrating, and I expect it to be completely gamebreaking in combat as it prevents me from turning sharply, or even turn at all if I'm not careful how fast I move my hand.
I have tried every combination of settings I could think of, both in the game's graphic options and in the Nvidia control panel. Nothing I did would solve the problem, but in general lowering the graphics would increase the maximum turn speed before the camera locked.
I have an Aspire 5738ZG laptop, with a dual core Pentium T4200 @ 2GHz, Windows 7 64bit, 4GB ram, and a Geforce G105M (512MB ram). All drivers, DirectX, PhysX, etc are up to date. FPS wise, the game runs fairly well on medium settings, and very smoothly at the lowest possible settings (note that I haven't progressed past the zeppelin at the very start of the game).
As far as I can tell, the "maximum" camera speed before locking is tied to the framerate: with the graphics on low it's almost impossible to reach that speed, at least until I enter the village; with everything set to high it becomes hard to turn at all. As for the FPS limiter: setting it to 30 made things a little worse, 20 seemed to bring a small improvement(oddly enough), 10 would exacerbate the issue. Multicore tweaks did nothing.
I should also note that when the camera locks, the game is not frozen: I can still move around, jump and punch, and the framerate seems steady.
I believe this is the same issue
detailed by Kasumimi since having a powerful computer would probably make it hard to notice outside of very graphically intensive situations, and easily mistaken for stuttering. I don't believe the issue is due to the 64Hz bug (microstuttering) though.
Well, I think I've said everything. I can't really hope for a solution seeing as the game has been out for so long... Still can't hurt to try, I guess! It's just too bad, Divinity 2 seemed such a promising game

EDIT: I found a suspicious line in the readme:
"Do not play with a NoDVD crack or with an illegal version of the game. The game contains hidden security measures which will degrade game functionality in case it detects a crack is being used. One example is the inability to jump, but there are plenty of others."
I can definitely jump, but the Steam version is recognized as legit, right?