Y'know, I'm not sweating the whole crowd/closure thing too much. Events like this are so different than a "typical" day at the parks, that it just pays to go with the flow.
I remember when we spent Millennium New Year at EPCOT, the parks were closed to everyone but Resort guests by 8 a.m. We had to show both our tickets and room keys just to get on the monorail. Granted, by the afternoon, they were letting people into the parks as other folks left, but we stayed put anyway.
We made the best of it and had a blast. Here's a swanky glamour shot from the locker room:
