I'm going to see it with my Autistic friend tomorrow, I was really looking forward to it but after some of his behavior I'm dreading it now.
First off, he has an OCD thing that he doesn't want "spoilers" about a film before he sees it, to the point of not wanting to see trailers, posters, toys in stores, magazine covers showing the characters, etc. If he sees these he does a big show of angrily covering them up, disrupting the store.
I was with him a few days ago and just tried to make conversation about the film, saying, "do you think there will be a space battle with x-wings", and he suddenly screamed "no - no - no" loudly at me. I said, I don't have spoilers, I just wanted to speculate, and he started screaming "no no no" in my face. So I took a breath and got away from him.
Second thing, when I saw Force Awakens with him, he was visibly excited, softly clapping his hands and gasping, bobbing up and down in his seat, when the credits began. This was endearing and I told our other sci-fi friends, and I embellished a bit, saying his eyes were bugging out and stuff. He was really loving this and keeps asking me to tell the story over and over of how funny he was watching the movie.
So I am thinking he is going to want to "out do" himself watching R1 and will be trying to climb on his seat or whatever attention-seeking stuff he has planned to show the theater how excited he is. : I