Our wedding was scheduled for 5:00, I think we got started a few minutes late, and the official time of sunset that day was 5:46. So 46 minutes to answer your question exactly, but it stays light out a bit longer than the "official" sunset time. We also had a clear day and a full moon.
For food we chose from the Menu Buffet. For starters/appetizers we had guacamole (which was served early during cocktail hour), caprese salad, and ceviche (which was some of the best we had down there). They also threw in some fresh bread. For our main dishes we chose the pineapple barbecue ribs (so good!), four cheese fettuccine, and shrimp skewers. For sides we had mashed potatoes, fried plantains, and grilled mixed veggies. The food was just EXCELLENT. So fresh, so delicious, great presentation and service. Our guests had a variety of tastes (husband and his family are very plain and picky, my family are big meat eaters, we had at least 3 vegetarians, and I love seafood) so I tried to choose a menu with lots of variety and something all would enjoy, and everyone was raving about it! We brought in dessert from off site. I had mini pies/tarts from Chez Celine, a French bakery/cafe in town.
For lighting I hung 6-8 strings of globe lights (Christmas lights I got from Target), and a few strings of Chinese lanterns. Attached to the ceiling in the palapa were two clusters of cylindrical lamps (see the pics for a better idea of what I'm talking about), which were already there. We also had a DJ, who provided lighting for the dance floor. As mentioned above, it was a clear sky and full moon for us, too, which I'm sure also helped. For non-lighting decor, I had papel picado banners, and there was already white tulle draping hung. Check with Blue Venado to see what they will already have in the palapa.
Some people may not be able to open the pics I attached my previous post. In that case, you can check them out here: http://weddingsinplaya.com/heidi-and-adrian-blue-venado-beach-club-playa-del-carmen/
Heidi