Originally Posted by Rapper_skull
You will maybe laugh at my reply, but I simply use WinRAR, on Windows, with maximum compression. I do not yet sign the ZIPs because I wanted to generate my own private key instead of using the generic test-key. What you can try to do is update your recovery (if it's not updated) to see if the problem is solved.
Using your information, I repacked on windows, not signed. And then my package did
work. Then I repackaged it on linux nog signed, and it did not work.
I inspected the windows-made package once more, and found at the the directories(!) were there not part of the zip file, while on linux they were. So I added an extra paremeter in linux not to add the directories explicitly, and then it did work, as long as I did nog sign it :P
So then I tried to resolve the problem: why didn't it want to sign correctly? And my feeling was that signapk.jar was breaking the zipfile if the zip was made on unix instead of windows (it kept changing some weird archive properties). So I searched for more ways and tools how to sign the zip. I did find another source, based on a shellscript and openssl, and by adapting their script to our needs I present to you: working, compressed and signed flashable zips
Update can be found in github, of course.