What you're describing is a problem common to all Facebook libraries, you need to create an application on Facebook and get an id/key (http://www.scringo.com/docs/android-guides/popular/connect-to-social-networks/), most libraries then require that you set it in the manifest. I haven't used this library, if you want to try using https://github.com/sromku/android-simple-facebook I can provide more help (if you need it, Simple Facebooks guide is pretty good), otherwise this hopefully makes it clear what you're missing
According to their quick start guide, Scringo it turns out also has it's own App Ids which you get through a dashboard, take a look here: http://www.scringo.com/docs/android-guides/quickstart/