The simple answer for RaceDeck installation is just that:
simple. The hardest part of installing RaceDeck is deciding what color(s) to get.
No need to start in the middle - all you need is a plan and a little time.
I had edge pieces all around my install, but I only had a 10'x16' "pad". If you're going to install up to the edge of the floor space, you'll need to leave about 1/2" (I think) for expansion. Not using edge pieces might look a little ragged, but I haven't seen many installs.
Yes - you'll need to purchase edge pieces for the entrance (at the very least).
If possible, I would recommend tiling the entire floor - including under any cabinets. Such considerations, though, are your call.
I'm sure others will have more opinions/advice. Just getting the ball rolling. Good luck on your floor!