Couple of bugs came to light today when in a 2 person co-op party. These issues occurred regardless of who was formed the party and, selected the mission.
Skulls - The 2 skulls with the sensor beam between them. Despite being destroyed, the models remain in place and, if either character crossed them the alarm was tripped.
Doors - The doors either end of the corner corridor that forms the gas trap and ambush. If the leader of the party goes into the room, despite the sufficient damage being dealt, the doors remain closed.