Models standing still while units move?

[Salkin]

Ran into this problem while trying to make a missile spell in JASS; the dummy unit does indeed move, as checking by turning locust off proved, but its model remains at the starting point. I'm pretty confident it's not JASS related, but have no idea otherwise.

 

[Cokemonkey11]

Set X and Y will bug out if the target has no movement speed.