1) I recently just finished installing the Dawnguard DLC and I quickly noticed two bugs. The first, and most severe is most if not all NPC's added by the dawnguard expansion are large white ! marks with a red aura around them. They are still interactable. The second bug is as soon as I enter first person view, it boots me back out into third person within a few seconds. I have tried running verify game cache through steam and it says all game files are correct.

2) The expansion content is nearly unplayable, I'd say severe.

3) For me to reproduce this, all I need to do is look at any dawnguard NPC or scroll/F key into 1st person

4) Intel Core i7 @2.2GHz, 8gigs of ram with 1 gig dedicated, NVIDIA GeForce GT 540m, 1920x1080, Windows 7 64bit.

5) Currently have all Mods disabled.

I found the solution to both of these problems and it quite the simple fix actually. All I did to fix these issues was simply create a new character. Not from the autosave of when you are about to customize the character, but from the start, beginning cinematic and all. It seemed old saves were not converting to the new content or something and making a new save with a new character somehow fixed the issue.

So just to confirm, once you create a new character and save. You can load your previous save and it'll fix the issue with my original character?

Right I tried this when I got home, The issue was fixed on the new save game but still appeared on the original Save. I'm not about to start over again. Hope this gets fixed soon!

A solution has been found to the 3rd-person bug, care of DarkenDE. For some reason I cannot post links on this forum, so: go read the 'Help me fix the Dawnguard 3rd-person bug?' thread over in the Creation Kit forum, specifically post #13.