I think the Screen explains most things :)

You can't fall off right or left, so you will feel like the real Mario.
There are flags and weapons and all stuff that's needed.
The question-mark bricks usually indicate jumppads to get up there.

I made it because I was quite bored, and the editing is far away from being perfect.
Just wanted to finish fast and be the cool guy with the Mario-Map at the next LAN.

Have fun and such. *Greetz*