Read this user guide before use.
Installing the package is the same as with any other Joomla! component. Go to your site's back-end Extensions, Manage and click on Browse. Locate the ZIP package and click on Upload and Install.
Joomla! Media Manager
Actually the component take advantage of Joomla! Media Manager, and it just expands it's capabilities by giving you the ability to add any file within your articles.
In order to be able to upload files, other than images, you can set it up in Joomla! media manager.