after long search,,,,,could not find and was end up with nothing
till i remember once, that i had rooted chinese tab vis some private app....
so i give it try on the Kindle HD 7, with the last OS 7.4.9,,,,and capooooooooom
it worked, and rooted.
try it for yourself
and then i used this link to make the kindle dual boot, so i do not lose the amazon feel.
let me know all