OK I had a further look at the problem and there was an issue with the moveTo command call. But I noticed something else that was tripping me up. I'm not 100% but this is my theory, if a creep moves into a room and you want it to move to the controller of the new room but the controller of the last room is close to the exit you just went through it seems telling the creep to move to the new room controller right after it goes back to the previous room and then the code tells it to exit again, so gets stuck on the exit.Only seems to happen on that one exit the controller is close too, so probably need code to get it to move into the room a few steps before telling it to head to the controller.Not sure if it's intended but definitely threw me off a bit.