I know
If the answer to my problem was in the Wiki i would't ask here

The problem is that no matter what i do they spawn no where near the objective, or the module doesn`t work at all.

I use a faction that does not have any helicopters. So the reinforcements arive by convoy on the ground. But they allways appear at the same spot.
I can't change the location where they spawn

Whenever I save my mission, and then load it, all vehicles I entered are where I entered them, and where left them at the end of the session.
The Vehicles are spawned by modules like the random empty ones Alive modules can place.