These are the sliders that will pop up to change Volume, Tone Length, and Sequence Length. To change any of these settings grab the little handle with the mouse and drag it up or down. You can test your setting by using the tuner on left (click on any of the six buttons). After you are satisfied click the appropriate Done button.

The sequence length refers to chords that are played where you can adjust the speed with which they are played. This may come in handy when you begin learning new chords.