How are deadlocks graph opened in Management Studio from Spotlight as of Spotlight on SQL Server Enterprise 8.1?
As of Spotlight on SQL Server Enterprise 18.104.22.16890, go to 'Monitor | SQL Activity.' At the 'SQL Activity' window, click on 'Deadlocks' tab. You'll then see a 'View Graph' button appear on the top right.
See attachment SOL92616_Fig_1_0.JPG.