I've had 3 Razer Nagas, and they all have the same problem: they are very picky about mouse pads. They all have problems with shiny or reflective pads or dark pads. For example, I have a bright red cloth one with some black stripes, and it freezes whenever the laser moves over the black spots. All of them will occasionally just reset the laser sometimes (one of them does it every minute or two, which makes it pretty much unusable).
I have had good luck with a few brightly colored cloth pads, but the best mouse pad I have used for a Razer Naga is -- believe it or not -- just a piece of white printer/copier paper taped to the desk. Tracks perfectly!