1. A couple goes camping with their son. The son disappears. In the evening, during a storm, the mother sees the son standing on the edge of the nearby forest, just staring at the camper. The boy is then wearing a white sweater.
I think it's a horror movie.

2. A young guy leaves home with a van, to go studying or working far from home. He doesn't arrive at his destination. It seems his van broke down and he got help from two men who passed by while he was standing next to the road, on an abandoned place. Apparently the two men were bankrobbers or something, on the run for the police.
The two men stole the van, killed the guy and dropped him from a cliff.

3. A couple is driving their car through the woods (or fields) when they're stopped by aliens, or people from a weird sect. They get undressed and have to take place in two separate glass chests, somewhat like phone booths. I don't know if they get abducted or tested or whatever.
I think it was a horror movie but thinking of the naked part it also could be an erotic movie. But since I saw the trailer during the break of a kid's movie it probably wasn't an erotic movie.

Thanks in advance!