A couple of clarifications for the DS event:
It doesn't matter what level your Pokemon are on. We will be playing in a way that automatically pulls your Pokemon's levels to 50. So don't stress if your Pokemon is on 45, and you can use something on 100, too.
Because of the way we're playing, every player has to have the C-Gear, which you get shortly after the first Gym. So if you haven't gotten the C-Gear, you can't play.