Suffering the exact same thing with shocking regularity: Any time I attempt to follow my friend, I will randomly die of 0 fall damage. This seems to happen most consistently on Tatooine's sand dunes, and can happen within 10 seconds of starting to follow. I have also had this plunge me straight through the game's mesh and into an infinite void abyss beneath the map. There is absolutely no possible excuse for the code for this function to be so broken in this particular way: Literally unheard of.