Game Center ReportScore & Leaderboard

Hi,
I’m adding Game Center support to my game using Unity 3.5. I’m working in sandbox mode.
Authentications and achievements works properly but I can’t report scores.
When I use this code:

Social.Active.ReportScore (scoreValue, "total_score", success => {
	        Debug.Log(success ? "Reported score successfully" : "Failed to report score");
	    	});

I got the “success” answer but the leaderboard is always empty. I’m missing something ?

From my testing, it seems that you have to have at least 1 friend in order to see the scores that were uploaded. Also, the scores don’t update immediately if you just try refreshing game center, but restarting the app and re-logging will probably show it.