Can I use a control created in Visual C# .NET or VB .NET within a managed C++ application?
Yes, you can. Using the control within a managed application is no different than it is using any other .NET control.
Can I create custom events for a control?
Even though it wasn't covered this hour, the process for creating an event is quite easy. You can use the Unified Event Model to create events, just as it is explained in Hour 18, "Events and Delegates."
Can I create a control derived from the Control class and then use that control in another control derived from the UserControl class?
Once again, the answer is yes. The UserControl class is meant to hold a collection of different .NET Framework controls, and because a control derived from the Control class means that it is a .NET Framework control, you can use it within a composite control.