I recently received new Add-Ons and as soon as I select to Manage Add-Ons, Xcelsius stops working and my PC completely crashes. I'm running 2008 release 5.1.1.0 Build 12,1,1,344. All I've tried so far is a full restart with nothing else running and deleting the registry. Registry does get re-created but the problem persists. Has anyone else had similar problems or have suggestions?