So basically I am stuck in dawnguard. When I get to Vyrthur sitting on his throne, he delivers his speech, and then all his frozen minions and astronach attack me. Then when he stands up, (presumably to disable the forcefield preventing you from reaching him), the game immediately closes, without any error or even a log (after enabling logging). I have tried using the console to advance the quest objective from outside of the room, but the forcefield remains, and tlc-ing through it to chase him results in him delivering another speech and then remaining invincible. Is there anyone who knows anything about this? Or anyone who knows how to trick skyrim into thinking the segment that keeps crashing has already happened somehow? Thanks!