I tested your map and I noticed this:
If you are too close to the door, you cannot interact with the door when you press the USE button.
That's why you need to interact at some distance from the door.
And when I compile map and pick up weaponbox, only gives me the 357 ammo.Actually, Weaponbox gives you all of it's contents.
weapon_handgrenade
, weapon_snark
, weapon_satchel
and weapon_tripmine
in time, the player cannot use them.