Just beat it today, and I have the intention of going back and getting as many of the items as I can, having originally ended with a mere 44%. However, there are some areas I cannot access. . . they're protected by the arrow blocks, the ones you need to pick up speed to break through. But there's not enough room to build up sufficient speed. Any advice on how to break these accursed blocks? Time is of ze essence! Not really. But tell me. Now.