To Downgrade follow the Donovan's Guide :
http://donovan6000.blogspot.it/2013/06/i...overy.html
Use this tool to prepare an USB Stick using the UEFI HP Tool then rename the USB
like HP_TOOLS :
ftp.hp.com/pub/softpaq/sp52501-53000/sp52509.exe
Here You go (F.14 Recovery Files) :
http://rghost.net/7srj2wLxC
Unpack this file and extract the files into and copy them into USB Stick
and follow the guide . . .
Now shutdown your computer.
With the flash drive plugged in, hold down the Windows key and the b key.
Press the power button while continuing to hold down those two keys.
After a few seconds, the activity light on your flash drive will flash.
You can now stop holding down those two keys.
The screen may stay black for as long as 40 seconds and you might hear some beeping,
but eventually a screen like this will come up !
Wait for it to flash your BIOS and verify the new contents.
Then it'll restart and your computer shouldn't be bricked anymore.
Let me know
Regards