From what I can see, you are missing the rubber sleeve that covers the joint when the bed is open. My 183 has a black rubber piece that is attached inside and to the bed door so that the mattress doesn't sit on the material. As to the screws not being attached, it looks like something is pulling on the material, ie, it is stretched too tight?
2006 Ford Explorer Eddie Bauer
2012 R00 183 delivered 2 Sep 2011
2012 nights camped = 27
2011 nights camped = 22