Just reached the point where I have to join the place to reload in ammo before destroying missiles launchers. BUT WHERE is that point to rebuild the stock of ammo for the squad ?? The green marker has diappeared ! Thanks for your help !

Well, you need to destroy the ADAT's before re-equipping, so kill all tango's destroy the adat's by ordering the airstrike, and move to the waypoin, where a chopper comes down to re-equip. Make sure all your buddies are alive and well, you'll need them.....

how do i call in an air strike

if you approach the adat, you see the airstrike come up in the controlscreen at the left of you screen (where you can select teammates) select the airstrike with the mousewheel, aim at the ADAT and click teh mousewheel (execute action button)
It is very common for people who remapped their keys to have trouble executing the airstrikes, on the other hand if you have attached functionality in windows to your scroll wheel that could block it too.
Good luck

I am having a problem with this part too. To this point I have done all my commands through the overhead map. I have all my key mapping set to default. When I am at the ADAT I can see my airstrike option over on the left of my screen and I can scroll down to it. Could some one tell me button press by button press what to do next to get the airstrike to destroy the ADAT?