The stone floors can be" tedious" (avoiding swearing here!!!!!!) i have two floors of them both suspended with iron wood and good luck in the one huge building (also with rounded walls) I Highly recommend placing every tile from the same attitude.. ie along its left side then the nexts left side and so on! then start next row of tiles check each "4 corner" it will look nice when correct and make a neat " + " use a lot of wood framing to position yourself in right attitude.. Yes i sound pedantic but when the second tiled floor and columns dont stay up it can all be down at the base with a slightly uneven foundation. You find problem in that approximate area below breaking tiles.. GL!