Took a while, but I finally have the kart model re-shaded:
The image on the top is before, and the image on the bottom is after.
Now that that kart's finished, I'll start by adding my mascot character to the game:
While I work on stuffing her into the kart, feel free to suggest more characters. Remember, they have to be from a klik game. I've updated the project description with a list of all the characters suggested so far.