Bobcat,
The mid pole lines certainly helped to keep everything centered. The way the jib luff tension was run (to port bridle/hull intersection, then back to front beam) there needed to be something on the starboard side to keep the entire bridle/pole intersection from bending to port when the jib luff was loaded. We tied the port side first with the pole bent ever so slightly to port, then tied the starboard side tight to hold the pole as firmly as possible on the centerline. As to diamond wires, they were set at about 30 on the Loos gauge, in hindsight maybe a little loose, we weren't expecting quite that much breeze. I stayed on top of them, retightening as many mornings as time allowed. No one but me touched them during the regatta. If you have any other questions regarding how we set up the boats please ask, although I would not proclaim to anything close to an expert. We (Jake & I) decided how we wanted to tune the boats and I tried to keep them as close to those settings as possible during the event.
How do you like the boat? They look like a blast. I actually got to go out on the water on practice day for a few minutes to watch.