I did exactly what you told me to do
, at least I think I did:
Copied the developer.keystore file from this thread to the launchpad folder
Copied the two files you uploaded to the launchpad folder
Unplugged the kindle and pressed 'Shift Shift Space' to update the launchpad log file.
Pressed 'Shift L K' to run your script
Got the 'Failure' message from Launchpad.
Tried to play one of the games anyway just in case it had updated (snake and one other)
Nada, but KIF still works (this is why I think there were no changes)
There is no developer.keystore.backup file in launchpad either.
The above happens with all the different loadkeystore.sh files you posted here (including the latest).
I also tried Inameiname's method as well, and got the same (non) result.
I hope that's enough info. If you want to give up that's fine. This has probably wasted a lot of your time. It's just a shame. It would be good if non-hackers could also use all this beaut software.
I am looking into how to create an update file, but there doesn't seem to be any easy to follow steps for a noob like me. Though I think I may need the java runtime first.
EDIT: It seems that everything I need is here:
http://www.cowlark.com/kindle/getting-started.html
I'm just not sure how to use it.