Not a buggy time - you should be all set. We were there the second week of March last year and had no problems with the bugs. The resort info you receive at check in mentions the "no-see-ums" and states that they tend to come out during the more humid and warmer months when the nightime temps are above 70 degrees.
Daytime temps last year were great - high 70's to low 80's. The ocean was cool but we still enjoyed the beach and the pool plus all the activities. The sun is still VERY strong and many members of our family (12 of us in all) got major sunburn so make sure you use sunscreen. I used SPF 30 and had no problems - I'm fair though.
Evenings are cool (not cold)- bring a light jacket/sweater. You may even find pants appropriate. It was very breezy when we were there but the coast was feeling the remnants of a storm that had hit us up north earlier that week so that could account for the wind and cooler ocean temps.
Have a great time - and feel free to ask any more questions.