I have not tried it out either.

About adding friends that are no Facebook friends (that is indeed difficult). If you are both on the same server, you can try these options:
1. Look in the cup competition for teams in your friends league. If you found such team, click on it, go to "standings", click onto your friends team and send him a friend request.
2. Put a player you don't need on transfer market, your friend should then look for that player (reloading the transfer market helps) and make a bid. Then you can see that he made a bid,access his profile and send a friend request.