I have a room set up with sarcophagi prepped for ambush. Since I laid out the dungeon before getting to the ambush tutorial, I created the ambushed from scratch after studying Warehouse Ambushes. I have a LvlDraugrAmbush linked to DragonPriestCoffinMarker which is linked to NorSarcophagusTopAnim01. The ambush works properly, except that the draugr come out of the coffin before the lid has popped off. What's causing that and how can I fix it?