[Cecil]

IIRC, you also need to set the IP of your computer to an address somewhere along the lines of 10.xx.yy.zz. I typically set the zz to 15, as i know nothing on the robot network runs on that address. The use of a crossover cable shouldn't matter much, because most modern computers can tell the difference between the two and switch itself software-wise. I have always flashed ours with a straight-through cable.

If none of this helps, try booting the cRIO into safe-mode. Once it is booted, see if you can see it with the imager. If this works, flash it once in safe-mode, then reboot it normally (non-safe mode) and flash it again.