Import your music files into Movie Maker 2... drag them to the audio/music
track of a project's timeline.... the Save the Movie.
When MM2 sees that you only have music and no images or video clips, it'll
give you some choices of audio files. Pick one and it'll make a WMA file.
Then use that in PhotoStory.
The WMA file might have 5 music files in it and play for 15 minutes.... to
PhotoStory, it's still just one file.
--
PapaJohn