I've seen the battery for CXP it's all crazy and green looking, and there is barely any room to put it in. It comes with a PEQ box why not get a smaller 9.6 or 8.4v nunchuck or mini batt and put that in, The stupid green battery isn't suppose to go in the little box. And the Dust Cover popping open just means the lock is loose, which is happens in all "Dust cover popping" armalites. They eventually get loose or the locks wear out. And your bb's not feeding just means that you need to wind the hi-cap mag, like stated before if you want non-feeding action get yourself some mid/lo caps.
"Don't you know the first law of physics? Anything fun costs atleast $8"