I haven't opened our kit yet, but the FFG OP Guide is very clear that the store gets to decide the tournament format. Swiss is the recommended format, but even that is only up to the point where the organizer decides to start running elimination rounds.
FWIW, our tournament will be Swiss.
Is this the OP Guide to which you refer? Regardless, this document does clear state the although Swiss style is preferred, the TO is free to choose the tournament format.
Yep, that's it.
The Store Championship kit just has a single sheet that basically refers you to the OP rules on their site. The tournament doesn't have to be Swiss.
I ran 4 rounds of Swiss at my FLGS, and it turned out great! We had 24 players (double what the store employees told me to expect), so I had to do some quick shuffling around. I was greatly aided by one player who had just moved out here from Texas, and brought 4 of the GF9 mats. Combined with the 4 mats my brother and I brought, we had most players playing on some purty surfaces (thanks for the help Kevin!). After 4 rounds of Swiss, we only had one player with 4 wins (all full Wins). Places 2-4 were all 3 Win players, with order determined by Strength of Schedule. Worked great, and we had lots of players swapping emails at the end of the event, so I think that's a win for everyone!