The difference between an abridged and unabridged book can vary greatly depending on the specific book. By definition an abridged book is shortened. Unabridged books by definition are unaltered and in their original state. They are exactly as long as they were meant to be from the beginning. Abridged books will be missing content that was included in the original unabridged version.
]That being said, I'm unclear as to how you could possibly abridge an animated anything. I'm assuming this will all be audio and there is no way that you can portray the actual movements in the original animation. The old adage, "actions speak louder than words" doesn't apply here because you can't see what the characters are doing. This means that you will need to add a narrator and write the visuals. So really you wouldn't be abridging anything. You would have to revamp and have it unabridged.
I am currently (thinking about) working on a fanfic that is heavily influenced on that series. So maybe we can help each other out somehow. Hit me up at firstname.lastname@example.org if you'd like.