ORIGINAL: webbclan
Siman,
The way I understand it is that the external battery kit is used to extend the life of the camera battery(s), so you would have to have the batteries in the camera. The batteries in the camera are the primary source of power with the external kit simply supplementing that source.
not true. you can just use the 12v battery kit (that's all i ever use).
siman - do you have a voltage meeter? your battery should be well over 12v, i think mine charge up to about 12.6. sometimes I have to twist the plug where it plugs into the camera. also make sure you turn it on

. oh, make sure that when you close the lid on the case that the terminals are still connected to the battery - you have to be carefull when closing the lid.
one more piece of advice - these cases are not waterproof. i always hang mine upside down so the water doesn't accumulate inside the case. i don't know how many times i've checked it and it was completely full of water.
anyway, good luck. hope it fires up for ya!