Thank you guys so much for your explanation! I really appreciate your work to help others!
I followed all the steps, and I think I JB my PW4. The Kual document appeared on the home screen, and that's great, cuz I didn't brick my Kindle.
The only problem is that I don't know what to do next. I try to put the .bin files (Python, Screensavers hack, font hack, etc) into mrpackages folder, and then I open the Kual to install them, but after loading nothing happens
Am I missing something?