First: you're confusing a lot of stuff together, which probably doesn't help, So I'll try to keep it clear & concise.
That said:
* You're jailbroken, that's good.
* You're confusing the device jailbreak with the Kindle jailbreak/dev-certs. Forget about the keystore stuff, that's dev-speak, as an end-user, you shouldn't ever come face to face with it. (TL;DR: the stuff you did on the USB root about that will probably be seen as funny by a few people, but is ultimately wrong & useless, though not harmful
).
If you need to use Kindlets, like KUAL, just install the prerequisite packages.
* Now, about the screensavers hack. Nope, it has nothing to do about your Kindle model/version/serial (which I just obfuscated in your original post, because you probably don't want that out in the open
).
You're also mixing a lot of different settings together, which doesn't help.
To go back to a sane state, I would:
* Uninstall the screensavers hack.
* Remove the linkss folder
* Install the screensavers hack
And STOP there. Check if it works, there's a default custom screensavers installed for this particular reason.
If it does work, good. Read the doc again to figure out which features you want to use, and then use the KUAL extension to enable them, forget about dropping files in the linkss folder like a madman
.
If it doesn't, check the
FAQ, with a particular emphasis on 'Is this a Special Offers device?' and 'Did it come from Waterstones?'.