Update: Thanks to Tardii for pointing out below that this trick still works after the Mango update, although slightly differently-
Play through the final Zone without getting hit in Score mode - If you do get hit, press the 'Windows' key to return Home. Instead of pressing back to resume, start the game from your games list. At the title screen, choose to resume from last checkpoint and continue from there. Repeat until you finish the level without getting hit.