1. I managed to go offscreen to the right of the first level (past the level end thing) by hitting the trampoline like crazy
2. When I beat an enemy, i just start at the beginning of the level and the enemy is still there
3. Once, after speeding up on a green ramp I went so far into a wall that I got stuck (this happens a lot)
4. Restarting goes back to the first level

Platforming is fun though