Tips: *Left and right arrow keys change the selected beat faster than clicking the buttons. *Setting no song name will prevent a message to come up in the chat in Minecraft when the song is played. *The ticks variable in the bottom left corner changes the time between one beat and another. *Changing the add mode to "Add to selected beat" will add whatever notes you play to the selected beat. *Changing the add mode to "Play without adding notes" will not add notes when you play the piano display. *Don't share your saved song code if you don't want it to be copied. Share the command instead. *There are eight available instruments that can be changed through at any time. Feel free to try them out! *You can have multiple instruments in the same beat with the "Add to selected beat" mode.
If you want to post your own songs or view some examples, go here: https://scratch.mit.edu/discuss/topic/265436/?page=1#post-2667832 Here's the post where you can download the function files for your Minecraft world: https://www.planetminecraft.com/project/custom-music-for-mc-1-12/