My ceremony was indeed at the Wedding Pavilion located in between the GF and the Poly. We used chartered busses to transport our guests to the reception (this is required by Disney when you have an in-park reception since the busses actually take the guests into the park through the back cast entrance). Our pre-reception was an Illuminations party on the Italy Isola (the little island at the Italy pavilion), so that took place in between the ceremony and reception. Our actual reception in the American Adventure Rotunda did not begin until around 9:45 after Illuminations was over. I am not 100% positive about this, but I believe that Disney does close the American Adventure to guests a little bit early to allow time to set up for receptions. It was a requirement to have a late reception to use that venue.
You guys looked great - were the pics that were taken inside the GF taken the day Beth (Beauty) and I saw you?