This will probably be of no use to you, but I had no trouble using white balance for NEF files I created on my new D800 using darktable. Darktable is powerful raw image processor which works under Linux. Since I work mainly under Linux, I have to use it, and I wondered how well it would work with my D800. It worked pretty well with my D90, and so far at least it is working with the d800.
Leonard Evens Professor Emeritus, Department of Mathematics, Northwestern University