Dear omgmog, could you please add a reminder for absent-minded ppl (such as myself) to copy over the system directory right after this part:
If you're currently using a firmware version lower than the version you've modified, you can do this quite simply by putting your modified firmware on to the root of your Dingoo's internal memory, named as 'a320.hxf', and booting the Dingoo while holding down on the d-pad. This should start the updater, and flash your firmware.
And now for some heavy unbricking..

Many thanks!