Each time you connect your iPod to your PC, it would check for updates if online. This is a problem, because after a iPod firmware update, it does not work properly with the MP3 Maker any longer. This is a stupid game initiated by Apple to keep us away from using other software than iTunes.
This is affecting each audio software except iTunes.
The MP3 Maker version 12 is too old to handle current iPod firmware. Try the version 14 - it will work then. But as any other software (except iTunes) it won't accept the iPod Touch, iPhone and the like.
If I understand you correctly, you want to import an audio file from ITunes to use in MP3 Maker. I have tried this using Music STUDIO and ITunes did not allow it. The work around is to use ITunes to create an Audio CD of the tracks you want. You can then import the files using the File | Load/Import | Load audio CD track(s) command. This works on Music STUDIO. Hope this helps on MP3 Maker. If you do this a lot, you might want to get a rewritable CD.