i) How do you use the supply truck, is it like searching a body?
Exactly the same hit X it will then give you the eye cursor, then go in the truck and take what you want.
2)Do you have to supply each and every individual? or is there squad re-supplying?
If you select a squad move it near the truck then when it is near just DBL click whatever it is you want and it will distribute it amongst your team.
3)Why do some units just become immovable (when clicked a red x appears)?
If there is a red cross on the units then they are AI units often in the maps you have permanent AI defensive units these have the little red cross on them. --- I Look Like I'm Pro But I Quit When I'm Losing To Pad My Stats - HOOFARTED