Automatic is a panel of preferences that you can use to automatically download the files that are linked on any RSS feed according to given regular expressions.
All you have to do is decide how often Automatic should check each feed for updates. You can also decide where the downloads are stored, though Automatic recommends selecting the same download directory as your P2P application.
Next, enter the content of the feed to which you want to subscribe. You have to add a regular expression in order to filter everything, so you should probably take a look at the Quick Start Guide & Tips file that comes with the application.