I've seen a few photos of the tower, though I can't quite remember where. Tyranid claws and a few other Tyranid bits are used as decoration, most of the rest is a fairly simple, flat pattern. It's based off a similar tower made for Warhammer, and a 'how to build' for that tower was once part of the GW website- sadly long gone now, but possibly able to be found elsewhere? I think I remember that the Warhammer scale tower used soaked and bent bamboo skewers for support.
For the fortress itself, I don't think I've ever seen other photos of it.
