As long as you dont turn the ignition on you should be ok, if the ignition goes on the glow plugs will pull a good 60 or 70 amps!!
The central locking motors will spike as well..
I think from memory the courtesy lighting will pull 3 - 4 amps.
When the car is asleep the draw sould only be 20 or so mA, or 0.02 amps, if the hazard switch comes on and it wakes, it'll probably pull around 0.6 - 1amp.
Last time I had a similar problem the draw when locked and asleep was about 20mA, low enough to notice the led in the door, you might see the meter flick between 0.02 and 0.03ish as the led flashes..
I seem to think that the ccm supplies the door lights with a positive, and switch them on the negative side, npn style. The water in the door harness could well upset everything. Without having in depth circuit diagrams of the ccm and details of how its programmed it hard to know exactly how it reacts, but it certainly upsets something..