Most people try to login with the wrong user name,
Click on "Forgotton User Name" (top right) and enter your email
Didn’t get your username? Check your junk email folder.
Got your user name, click "Forgotton Password" (top right) to get your password
Now you have your user name and password login to the system
Now go to TOP MENU > COMMUNITY I COMMUNITY MENU > PROFILE > MY PROFILE go to the bottom of the page hit the associate my account with Facebook button.
That’s it – now you just need to press the Blue Facebook button to login in the future. You are welcome :-)