I get this error from the 2010 visualizer
System.InvalidCastException: Unable to cast object of type 'SD.LLBLGen.Pro.DebugVisualizers.EntityCollectionVisualizer' to type 'Microsoft.VisualStudio.DebuggerVisualizers.DialogDebuggerVisualizer'.
at Microsoft.VisualStudio.DebuggerVisualizers.DebugViewerShim.ManagedShim.DelegatedHost.CreateViewer(IntPtr hwnd, HostServicesHelper hsh, SafeProxyWrapper proxy)