when you did the short trick, you said it did not work. why?
at which point did it fail?
what did your terminal return when you ran script?
you will never get this fixed unless you provide more info.
apart from the brick which Adeel mentioned above I yet to know of a fully bricked kindle (they seem to be pretty bullet proof).
I am presuming that you took a short cut in setting up the firekit.
Gnex: Dreams 4.4 KitKat
Kindle Fire: HashCodes CM11
Nexus 5: SlimKat
If you like my work or think I have helped please hit the thanks/donate