Hint : In the 2nd level check your mistakes on the top-left (it's not a misplaced death plane)
Going negative on the mistakes counter is supposed to be a fail state. This level teaches to avoid some collectables.
ARGH! Dumb me, I didn't get that... I'll never learn!
We didn't have time to explain it properly. The 1 hour time extension was crucial for us to finish the game