That really is some great stuff there. I love the shading you got going with every edge of a wall. And the roof tiles are awesome. I like how run down everything looks and the edging on the broken roof. But I'd say the broken walls should look more eratic than a blatent "missing square" look. That would work for a stone castle but not these walls.
I wish people would learn how to rate scenery properly. Very nice peice, with a top notch paint job (rare to see multi tone painting on things like this). The broken walls are a little too straight for me (I guess you were trying for the broken block effect) but overall its great.