You must have Music 1 Version 7 installed in order to use this upgrade.
A few minutes after you fill in the form, check your inbox for an email with the link to the upgrade. Save the file to your desktop or to your downloads folder. When the download is complete, be sure Music 1 is not running, then double-click on that file, then click the Unzip button and it will extract into your c:\music 1 directory and overwrite the earlier version. The upgrade file can then be deleted from your computer.
If you are running M1 on multiple computers, move the M1upgrade70.exe file to each one and run it there. It is important that each machine has the very same version of the M1 engine.