Hello Elizabeth,
Can you download them to your computer? (they will probably show as a number) but as has been suggested, you could then copy to a new SD Card, and maybe that will download as per usual.
However, you will have to load each file/song and rename it or, it could be quicker to mark the number and name on your music that way, you would be able to tell the audience the title of what you are about to play.
Just a thought!
Audrey