How it works
If you were to add a field to the Audio module via the Form Designer which was called 'audio_download' that only the admin user was able to turn on or off. Then use the Parameter Injection
module to check that the state of that form field was set to allow the download of that particular album, then that would be one way this module could be used.
The module is for very specific use cases so outlining all the possible ways it could be used is difficult.