I gave up. Waiting for better solutions.

i got the same KP as OP
how do i repair the mkext permissions?
i am using chameleon rc1 + efi10 boot file + snowleo upgrade disk to a 8GB flash drive



EDIT:
nvm that still didnt work.
trying to firgure out :/

OS : Windows 7 RTM + iPC 10.5.6 + combo update (vanilla)
Mobo : Asus P5N-D (750i Chipset)
Cpu : Intel E8400 @ 3.93 GHZ (on water)
Ram : 4gb (1GBx2) (2GBx1)
HDD SATA : 320GB
DVD-RW IDE : PLEXTOR slotloading DVDRW
GFX CARD : nVidia eVGA GTX260 Core 216

Ok!
So I found out what you have to do

delete the mkext file in the extra folder. It's only for speed and not needed!