These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Moral Event Horizon - Not only does Mr. Cosmo cross this, he quickly moves miles away from it. The crowning moment of this is in many of the scenes involving him and Snap. His treatment of Snap is downright abhorrent and cruel.
Nightmare Fuel - The horrific treatment Snap recieves qualifies as this.
He has a hole dug into his head while he is awake.
He is forced to fight his friends via mind control device while he is fully aware.
His feet are horribly burned just to send a message to Rudy.
What Could Have Been - The author originally had different plans for the story, and had she kept to her original intentions, the story would have turned out quite different.
The original plot of the story would have taken place after communication between ChalkZone and the real world became commonplace, and would have dealt with zoner slavery to an extent.
In another version, the story was going to involve Rudy and Penny trying to stop Mr. Cosmo from exposing ChalkZone, but he succeeds, and the rest of the story would have dealt with trying to undo the damage.
Originally, Ms. Saffron was supposed to be the same level threat as Mr. Cosmo. The author, at one point, considered making her the main antagonist rather than Mr. Cosmo.
Snap was not supposed to get that badly hurt initially, and was to aid Rudy throughout most of the story.
The author had considered ending the story with Snap never regaining the ability to walk. She decided to scrap this idea.