Use the arrow keys to move. It might look like somebody spilled paint, but move the slider on top to the right, and you can mess with the controls, or edit the map. You can use your mouse to draw and change the variables to change the color. Once done, hit the flag to start it again and there you go.
Base is from Finlay_Cool's Super Mario Kart game. I deleted intro, activated debug camera, compressed into two sprites, made a debug mode with access to the variables, and most importantly, made a editor.