I've seen a few ads for this and came to pop a wish-list on it. However, in everything I've seen I've not seen anything but flat ground. Is this a limitation of the software? Can I not build a city that sloes up a hillside? I can see that being an issue with 3D printing... though I doubt it's impossible.

Most of my fantasy worlds are quite hilly and mountainous. It would be nice to use this to craft some of them. I have, for example, a dwarven bridge city over a chasm atop a great waterfall and various shanty towns clinging to the cliffs on either side... Without verticality that would be a problem to model.