Anytime after they open (9am) and come over to the group shelter whenever you want. We'll be setting up or hanging out. You can join or go enjoy the sandy beach.
The park attendant can give you directions (tell them you are there for the wedding). There are also signs for the group shelter. But if you insist on knowing ahead of time: after getting past the gate, go to the left at the fork, then park at the first large dirt parking-looking area. The group shelter is down a path towards the far end.
Yes there are, but let them know you are there for the wedding and your fee will be covered. (Please let them know if you are over 65, active duty military, children, etc).
It's a wedding on the beach - wear what makes you comfortable. The bride plans to wear a white sun dress (or possibility a white top and shorts if she can find something she likes). The groom will likely be in khakis and a "nicer" shirt.
Are you seriously asking this question? It's a wedding on the beach - yes kids are invited! In fact they can leave their parents behind if they want! The after-party will not be appropriate for them as it is both late and primarily based around alcohol.
Yes, just please let me know so I can have a somewhat accurate count for food and drinks.