As kcashner said, the key is to have all your reservations linked together now. That will insure you sit together at dinner. We had 22 in our group in November in 8 rooms, and ended up with 4 tables (table #s 1,2,3 &4) They were all in the same area with the same servers, and each night they did their best to connect as many tables as physically possible. We were still at two or three tables, but side by side or back to back. With a group of 13, you should be able to join tables into one long one or two back to back. Even though each room had a specific table assignment, we moved around each night to sit with others in our group and that was never a problem.