So I've been really annoyed by this... I've reached the final mission of Dawnguard, where the Dawnguard and I are about to launch the assaut on Castle Volkihar... BUT. Every time I go there, I find the Dawnguard waiting near the Castle, but the vampires and Death Hound won't spawn. The two Gargoyles break out, but that's about it. Since the rest of the enemies don't spawn, the door into the Castle won't open, so basically it says: "Castle Volkihar (Requires Key)". Which is a key i obvously don't have, as it's supposed to open after killing all the enemies outside (that refuse to spawn). So I was wondering if any of you have heard about this before, and if you might have a possible solution? Kinda annoying when I've played through the whole questline but end up being unable to finish it. Thanks!