I was a little worried about the see-through part, too, but the dress is supposedly lined (maybe they make the runway dress a little sexier? here's hoping). Anyway, if I'm going to be showing more of Laura than the FILs want to see, I'll have to get creative with the undergarments.
Anyway, as far as down time, we've actually got like 8 hours between the two events, but I'm going to put some tulle in our wedding colors up around a few palapas, and just have our guests hang with us on the beach and drink margaritas. Then we'll all go and get cleaned up and meet for cocktail hour.
It's not very traditional, but I just wanted the day to feel like a big party where everyone was important, not just us.