It's probably the perspective, but when I saw this on flickr last night I thought it looked like it was in microscale.
I love the wooden sentries dotted around the castle, and from the modularity photo it's evident lots of both work and planning has gone into the build. The arches and various decor make it all the more interesting.
What I will say however is that along with all the tiling and the pure grey walls the castle seems a little too "clean", maybe even artificial. The wooden elements really help break that up, but another colour in about the walls and stonework would work brilliantly, though i'm sure some would disagree with me.