There are numerous ui bugs when in co-op.  Firstly, all equippable items and shards take up 2 slots in bag inventory.  Secondly, the interact menu will only pop up if the the item is unequipped in the bag inventory.  Third, you cannot change bag options while in coop.  Fourth, not final because this is only the first night, the end match screen is cut in half and focused on the right hand side of both players screens.  You cannot see anything besides replay map.