Use the arrow keys to navigate. Avoid the red and try to get to the right edge of the screen to advance. Press the 1 key to show the list of high scores. If I create any platformers in the future, they will likely use this engine to do so. There are so few levels because this is a template for a game, not a game itself.
If you want to take scripts or remix, please give credit where credit is due. Not only to me, but also to the person who gave me the base for my current gravity script, @shadow-coder