You should be able to figure out the game based on the built-in help, but there are a few hidden features.
First, there is an intentional bug related to the springs. You will need to figure this out to get past about 30.
There is also a "hard mode" - press Mode at the title screen, then quit and restart the game. The difference is only in appearance, but it does make the game harder.
Finally, for the 84+, there is a delay option. Store a number to LSTARS(4) if you need to slow down the game - I recommend starting with about 5.