Most of the wedding party cast actually stayed in the villa that they filmed in.
The scenes on the river were filmed on a tidal bank on the river Tarcoles. The tide covered the area faster than anticipated and the crew had to abandon shooting and find another spot to finish the scene. You can see the area disappearing underwater in the background of later shots in the scene.
Director Colin Theys spent several days hiking through the forest alone to find the locations for the jungle scenes.
The secret beach location was only accessible by boat, but when the crew arrived to film the scene, there was an entire rowing class and two large family parties on the beach.