Good progress, this one is coming along nicely. Couple of suggestions - I would add some type of 'trim' to the wall next to the wooden door. And I agree with Graywolf - making the debris more representative of the wall would make it look contextual and as if the debris came from that specific wall. I like the look of the break on the left most board of the door, if you could reproduce that on the other doors I think it would enhance it a bit, don't forget to put the door debris in too.
Overall, looking good. Nice/interesting subject, I like the vertical feel and the multi level appearance.