There are two links here. If you are installing Music 1 SE for the first time on the computer, you'll need both. If you already have M1 installed on your computer(s), you need only the upgrade file.
To get the upgrade file, click HERE.
Download the file named seupgrade70.exe. Check to be sure M1 is closed, then run the file and click the button: Unzip. A message will pop up saying: 3 Files unzipped. and you are done. Run and unzip the file on every computer where you have M1 installed.
To Install Music 1 on a new computer, download the installer click HERE.
Run the m1setup file. Choose the 'minimal' install option when you see the choice.
After the install, run and unzip the seupgrade70 file.