Even though I successfully debricked my Kindle after the failed update with Amazon's 5.1.0 update package (most probably not their fault but because of tinkered with root partition) I wasn't able to get a working 5.1.0 by using the official update packes with the debricked 5.0.0.
It would install the update but after reboot it would go to the "Your Kindle needs repair screen" after a while. Strangely, using a USB cable would still work and after removing it, it would go straight to the normal home screen.
So I thought, try out the forensic 5.1.2 images, flashed the kernel and the mmcblk0p1 5.1.2 (main+jb+kjb+ssh) image. But this time it even just went to a black screen after reboot.
Any ideas what's up with that? Oh, and BTW, I always cleared the /var/local partition.