This song uses a Custom Block which converts a piano note(letter) like C or F# to the scratch system of piano keys(from 48 to 72). You can also enter the scale and the beat to play it. To use this for your own song replace the list song keys with the keys of your desired song, press b and type a beat value to make that the number of beats every single note is played for(you can later change the list called Song Beats to make it such that different keys are played with different beats)
To add a pause between two keys insert an item(in the Song Keys list) and type r with the value you want, eg.: r1.2 or r1 (it can take as many decimals as you give it)