You'll also need to download the attached music editing software. I've provided an executable but if you don't feel like running random software from the web you can also download the source code - compile it yourself or take a look how it works. It's all in C# so Visual C# 2010 Express is what you'll need. This software will let you edit your tune and generate the custom gcode to engrave it on the blank acrylic sheet.
The software is admittedly pretty basic. It's not exactly sophisticated music editing software but the player is not exactly hifi equipment. It does the job and I hope you'll find it easy to use.
Click where you want to add a note and click again to remove it. Click on the blue + if you want to add a gap. Click on the red X if you want to delete some notes and shuffle everything up. Click the Play button to preview your tune.
The left hand side of the musical stave shows all the note that the player can play. You'll find they are most of the notes from a C major scale and cover about 2 octaves. There are no sharps of flats and a few notes are missing. I guess that's because the original 10 nursery rhymes it can play just didn't need them.
Once you've finished your masterpiece (or more likely transposed someone else's tune) it's time to create the physical product. Click "Build / Create GCode" in the editing software. Three gcode file will be churned out. The will engrave the musical track and cut out the disc. The gcode is just a text file with instructions for your CNC machine, but you can view the toolpath in CamBam if you've installed it.