what time do the doors open for 8 o'clock show?

I would have guessed 7pm. They do have drinks and snacks inside but it is minimal, so if it's assigned seating, your better of next door at Quinta Sol or further around the corner at the cafe on Theater Way which is a closed street.

I'm not sure but I think you can call and ask. There are plenty of bars and restaurants around it where you can go if you're early.

7:30 I think