I made it to play with my daughter, because figuring out how to do those X's was oh-so-much easier than grabbing a pencil and sheet of paper.
Seriously, though, it took a long time to get the X's, and they're still not perfect. Good enough for a 4-year old, though. They needed to be at a 45 degree angle and then line up enough with the square so that any jagged edges could be covered with a tile, but the tile still had to have enough solid brick studs to attach on firmly.
Oh, and every single piece is attached! Nothing is free floating at all (well, not counting the fact that the squares are removable for playing the game). Those guys over at twee affect would be so proud. ;-)
P.S. The whole time I was trying to figure out the X's, I kept thinking there was probably a very obvious way to do it, and I was just too blind to see it...