OAuth 2 + FB connect. How to use?

[eluser]Dani[/eluser]
I cant find any user manual for this. I need authentication with Facebook and also regular authentication for those who dont have or want to use FB connect.

I have installed OAuth2 from https://github.com/philsturgeon/codeigniter-oauth2 with Sparks. Then I copied the example in the link in a file named auth.php, just replacing the facebook id and secret and version number. I receive the user data from FB fine. So what are the next steps?

Should I register the user inside the try{}-block (as you see in the example) ? How and where in the code should I handle the option to select no-FB-connect ?