Play around with the knobs and press keys to play the synthesizer! Different knobs adjust different settings (master volume, tempo, instrument, etc.). Click and hold to turn knobs. Press keys on the keyboard to play the on-screen keyboard. Click on the KEY button to change the key that you are in. This will affect the auto-play system.
I will be adding a manual sequencer, more sounds (other than the default scratch ones) and part-specific volume. Please tell me in the comments if you have any problems or ideas. I know the instruments don't sound great and that is just because of the way they work.