Click the piano keys or use keys on your keyboard... w e t y u o a s d f g h j k to play the corresponding keys on the piano! You can even drag your mouse!
To record click on the record button, use the Spacebar to add a pause, it's really nice because it doesn't record your pauses, so if you get really stuck take your time! If you click the wrong key click the down arrow to delete it. Some instruments have to have a tempo of 0.2+, so is your confused why your tempo switched to 0.2, it's because the instrument you have needs to have a longer tempo.
