I have done JB on my KV finally. Folders extentions and mrpackages are visible in my kindle. JB ststus was tested with dummy installer and it was ok. Amazon update done manually to FW version 5.8.2.
Then via putting KUAL-KDK-2.0.azw2 into documents I saw KUAL in library.
While trying to launsh KUAL I got this message:
"This device is not authorized as a test Kindle by the developer of this item".
Then I deleted KUAL-KDK-2.0.azw2 from documents folder and tried KOA method. In other words I put Update_KUALBooklet_v2.7_install.bin into mrpack. folder and with :log mrpi tried to install KUAL. Nothing happens!