Here are the racetracks for Shell Cup.
DS Figure-8 CircuitEdit
While the layout of the track doesn't appear to change, it features more detail than the original. It now has glider features in it, and the background looks more likely to Super Mario 3D Land.
GBA Riverside ParkEdit
The loop now has a anti-gravity function so anyone can turn around it. Also, you can drive underwater, too!
SNES Vanilla Lake 1Edit
Description saved for TimeSoul.
Wii Toad's FactoryEdit
Description saved for RandomUser24.