If you attempt to call ShowDialog on a TaskDialog that you haven't added any buttons to, the call to ShowDialog will throw a NullReferenceException. Could this be improved to throw a more meaningful exception - or perhaps add a default button to it? Example: ``` var dialog = new Ookii.Dialogs.Wpf.TaskDialog { Content = "Message", MainInstruction = "Instruction" }; dialog.ShowDialog(); // NullReferenceException here. dialog is not null. ``` Thank you!