When i save my files they are saved in an aup format. How do i open the song as a single piece?
That’s an Audacity Project manager text file. To get a real sound file you have to Export one. if you need an MP3, you also have to install separate Lame software.
http://manual.audacityteam.org/o/man/faq_installation_and_plug_ins.html#lame
http://manual.audacityteam.org/o/man/audacity_projects.html
Koz