Hi,

There have been a few threads on this topic here. Make sure to download *all* the content packs linked from the "Help" menu and install them consecutively while Music Maker 15 is not running. If there is a particular problem with the installed soundpools (which are part of the whole content pack business) not showing up under the soundpools manager section in Music Maker, locate them on your hard drive and use the "Add styles" function in the soundpool section to manually import them into the soundpool database.

I hope this helps.