Deff. confirm your res. when you get to the resort if you have set things up proir to arrival. We did only to find something went wrong and they had no record of it. Couples, did however, step up to the plate and made all right. Turned out to be a very special night. We had the beach to ourselves.
Go to the Swept Away site. Scroll down to restaurants and bars. Hit that and go down to private dinner on the beach[ or something]. I think they want you to go to the romance concierge. The rest is pretty easy. Good luck and love it.
There is plenty of room on the beach for private dinners. When we were there in November there were at least 10 private dinners going on one night. If it were me, I would wait till I got there to book, just to make sure that the weather was perfect the night you book it. You would hate to book in advance, and find out that they are calling for rain that evening. Just a thought.