Im just trying to figure out how to fix our problem. We used liquid nails to hang the tiles. We tested it on a tile before hanging and it did not eat through the styrofoam so we used it to hang the majority of the ceiling and it was turning out beautifully. We ran out of liquid nails and ran to the local hardware store and bought the same liquid nails that we had bought before and finished the ceiling. The next morning we noticed that the new liquid nails we used had eaten through the tiles. The rest of the ceiling looks great! Now the tiles are sold out and we cant get more until July.