Not impressed

I downloaded the app after reading all the great reviews. Excited to start creating my ringtone I clicked on the song I wanted to use from my library and a message popped up "this song is cannot be used as a ringtone" Ok? So I clicked another song....got the same message. Tried it again several times and cant seem to make a ringtone from any of them. Im throughly disappointed.

daniraek about Ringtone Designer 2.0, v1.7