1.- Place your stock APK on the "modding" folder
2.- Run the Script
3.- Press any key
4.- Select your APK number (usually #1 if you have only one APK inside the modding folder)
5.- Press 1 again to extract it
6.- Go to the folder project/your APK goes here name/res/drawable ......
7.- Select your PNG's to modify
8.- After you are okay with the modding of the PNG's renamed them exactly as they were before.
9.- Put them back on the /drawable folder
10.- Back to the script and press 3 follow by 2 and then 1 to sign the APK
11.- Put it back to your SD and install like any other APK.
I don't think I'm missing anything here, but if somebody can chime in anything will be great too.