Has anyone out there ever installed a tin ceiling? We attempted it this weekend with bad results. The tiles are 24X24 and according to the directions received from American tin ceiling company, (where we got the tiles) they have little dimples on them to help with the install. Problem is, the dimples aren't in the same place on all the tile. Are we missing something. We chalked lines on our plywood and after only 8 tiles we were already off. Can anybody enlighted us?