I have been able to export mp3 files…but what happens when I’ve done it and try to close
that file, a box asks me if I want to save the changes I’ve made…if I say yes, it wants to make
an Aup file as well? I don’t understand. If the edited file is exported as an Mp3, I don’t want another
file of it…what to do?


Check that the MP3 file is correct before you close the project.
If you think there is a chance that you may want to re-edit the file, and/or create another MP3 with a different bit rate you should either save the project or export a (high quality) WAV file in addition to the MP3.
When you are sure that you want to close the project (and delete it forever), close the project and select “No” when prompted to save changes.

Thank you Steve.