At the end of the movie when Gerry is lying on his back, his legs change from flat to bent and back again. This obviously could not possibly happen due to his condition.
When talking about the lady failing on Wheel of Fortune, they say the person who solved the puzzle won zero dollars. In actuality there is a minimum prize per puzzle, usually $1000.
One does not hears owls hooting in the daytime.
Gerry uses his turban filled with dirt to make a soft landing spot for the jump. Walking away moments later, it appears to be spotless clean.
Obvious CGI landing when Gerry jumps off the rock.