The biggest problem so far is probably actually getting the weapons to spawn and equipping them. You didnt really mention how to do that aside from saying to include a button that adds all weapons to the slots, but how do you test specific weapons, how do you pick them up off the ground and so on and so forth.
I wouldnt mind if you sent me the blueprints to check out, It doesnt matter if they compile or not because of the null references.