Lots of good questions, gentlemen. All this is from Racedeck purchased during their black Friday sale. It was delivered within a week. Using the Racedeck website you can design anything to your heart's content. They figure out the number of tiles of each color. I have a dozen or so left over which I can't quite figure out why.
Contrary to instructions I butted the first row against the drywall but left 1/4 inch on the opposing wall. I used a table saw to finish the tiles on the last row (top and right). Sawing this is not difficult and they don't just melt like some plastics. You need face protection because the saw will spray you with chards of plastic.
As for the garage door, the sloped tiles did protrude under where the door comes down to the concrete. This 1/4 inch did make the door return to the open position. It was very simple to reprogram the door to accept the additional height and now it closes normally on top of the slopping tiles.
We installed the tiles in 45 degree temperature and I'm not sure if that made it more difficult or not. Perhaps if it was 30 degrees warmer the tiles would have joined easier. As it was, we had to kick many into place otherwise we used rubber mallets. It seemed to work better if we started hammering at the far end of the tile and then worked back to where it joined the two adjacent tiles. We definitely got better at it as we went along.
Yes, that's my 74 912 2.0 under the cover.