hmm. looks like a lot of the questions were not answered. Here is my take.
I ran the Cold Cathode lighting for a little while, it's too much light and I was not able to dim it. I'm back to using 25 watt blue bulbs. The dimmer would eventually blow out the 12V transformer. CCL can be dimmed but you need specialized ballasts made for the lighting that allow dimming, I could not find anything other than very expensive commercial products. The tubes are pretty cool to the touch, I would not worry about the heat it generates as it seem to be very little. The 12V is a transformer, as someone pointed out earlier in the thread, the CCL requires much higher voltage, so there is a little box included that steps up the voltage to make it usable with 12V.
Also the dim mod done by DJ88 was for LED. It would not work for Cold cathodes.
HTH