how did you make the emunand, usb loader gx?
i dont beleive i got neek2o thoughbtw, that's neek2o on the wii u, but it should be about the same method. push 1 and 2 at the same time over the disc channel. it's a little glitchy, but it works. also, you don't need the di file unless you're using disc backups I believe.
when I had this problem, the problem was the emunand. try creating one on a usb hdd.