Hold down the black button and pressing White will advance you to the next level, and will mark the level you just left with an S+. You can only do this to incomplete levels. Plug in a second controller, and press black and white on it, and you'll skip the level, but it won't be marked complete. But whatever you picked up will be counted.

Finish levels 1-1 through 8-4 with a "A+" or greater rank only. An FMV clip showing the game's developers will be opened in the "Collection" option.