Actually the only thing that happens after park closing is the first day private event on Friday, everyone waiting for it has been in the parks all day. The rest of the weekend goes on during park hours and is open to the public. They have all kinds of activities and guest panels along with the stars from the movie right there at the stage in front of Rip Ride Rockit and the area is like a madhouse. I've attended the last 2 years.for the harry potter weekend gala event, most of their activities are not in the park until the sessions are over.