Open Music Maker, insert soundpool dvd, if it ask where to copy? you can copy on Hard drive/external drive.

Or First copy your soundpool on Hard drive or external drive. Then start Music maker you will see:

Soundpool - File Manger - Templates - Keyboard - Inspector. Look under File Manger there will be +add click on it and browse when you locate the copied soundpool click on it and click ok.

Refer image.

Image copied from Magix.com