Do you have reserved seating

You can get reserved seating for tickets purchased in advance you have to select from what's available so when you go to the box office to pick up your tickets you already have your seats selected so yes they do have reserved seating

If you call them in advance, they might set up a private screening. Otherwise, it's for ticketed guests

Yes

Yes for the right price they will do a private screening.

I'm not certain about the private screening but ask them next time you're there so that way you know for sure but I know you can reserve your tickets pay for them with your card in advance and choose preferred seat