There is no reason to put a paintball gun in a refrigerator, or any appliance for that mater.
Which model? If it is the t9 or t8 pistol then you have to buy an adapter for a 20 oz tank.
if u mean the tank that you put your shoulder against and what powers it. no u can get co2 or compressed air (compressed air is better for your gun)
All guns leak a little bit when you put Co2 in the gun. its normal
Disassemble the gun, and replace the back cap with the stock or take it to a paintball store, and ask them to.
Have a degree in chemistry. Do not put anything in your gun besides air-tool lubricant (for mechanical guns), or actual paintball lube.
you screw the adapter into the gun, and then the co2 cartridge.
it depends on the model.
no, the rocking trigger was for spyder markers only
most likely a valve oring in damaged.
No. This is because the end head of the remote line does not have a valve. you would have to open the tank valve, fill it, close it, remove the remote, put it in your gun and then turn it back on. This would be more complicated then just removing the tank and filling it. If the remote line had an ending with a valve it would be easy, otherwise removing it would re-empty the tank.
Generally no, but it is important for proper maintenance that the gun be dismantled, cleaned, and lubricated after every use in order to get the most of out it.