Exception ticking HeronInvisibleDoor76688: System.NullReferenceException: Object reference not set to an instance of an object
at Verse.GridsUtility.GetThingList (IntVec3 c, Verse.Map map) [0x00000] in <filename unknown>:0
at RimWorld.Building_Door.Tick () [0x00000] in <filename unknown>:0
at DoorsExpanded.Building_DoorRegionHandler.Tick () [0x00000] in <filename unknown>:0
at Verse.TickList.Tick () [0x00000] in <filename unknown>:0
Verse.Log:Error(String, Boolean)
Verse.TickList:Tick()
Verse.TickManager:DoSingleTick()
Verse.TickManager:TickManagerUpdate()
Verse.Game:UpdatePlay()
Verse.Root_Play:Update()
