If you download the image, can you get openatv 6.4 working on the box, without grogbuild?tried again - no error flashed up this time - screen just we blank
wget --no-check-certificate -O ~/grogbuild-atv.sh http://www.dropbox.com/s/z8wqyrb1ig7vepd/grogbuild-atv.sh?dl=1 && chmod 744 ~/grogbuild-atv.sh && ~/grogbuild-atv.sh
yesyou do have a usb/hdd installed on the box that is initialised on the box dont you?