I understand how to make an ABS. Once you break it down it's not as hard as it is lengthly. The only thing I don't understand is making animated sprites, apart from having each frame as a seperate image.
I wouldn't be much help unless we were in the same room so... But there are others who are better able to explain how it works.
All I can tell you is that it is split into phases to make things easier to edit. If it was all one chunk of code, it would be a beast to search through. When it loops, the first thing it does is updates general things (input, audio, etc.) then checks for what phase it's in, and runs a method based on the phase.
EDIT : Just for clarification, I understand HOW to make an animated sprite, I just can't get it to work. I set everything up correctly, but it's not visible (z too low) so I try to increase the z coordinate, unfortunately it kept screwing up.