Explicit supply in El Alamein '43

[D-Day_Dodger]

I'm starting an El Alamein scenario using explicit supply. As the Allied player I have quite a few supply depots dotting the map as well as supply vehicles. However, I am unclear what role these supply depots play in the game.

For instance, assuming I can I draw supply from them, what is their supply radius? What benefits does the Axis player gain from capturing them in terms of supply and VPs? How do they affect Allied strategy (ie. are they worth defending)?

Any thoughts on this are much appreciated. Cheers.

P.S. Any other tips for fighting the Hun in the desert would be also appreciated.