I'm slowly working on trying to put together a bootable SD card image. I don't know for sure if this hardware supports booting from SD or not, but that is how you root and install a bootloader on a soft bricked Nook Color or Nook HD. it's a long shot, but I'm hoping to get a way to boot the C811 to a point where we can use adb to push the image files from the update manually from a command line adb shell.