It's actually not papercraft. The cubes are made of Styrofoam cubes with paper textures glued on. Papercraft cubes wouldnt work for something like this. They're too light, get crushed too easily, and cant be stacked easily
The block design we used in our gallery is not completely papercraft. It is paper texture printed and glued onto styrofoam cubes. The styrofoam is to reinforce the cubes so they have weight and so they don't get crushed by miners. I'll still post up my templates though.