I couldn't find anything in the book on activating tool tips for a form. I found a ToolTips class and examples in the MSDN help, but its a standalone method that refers to "this.components" as the "Form container", but this variable is null at the Form.Load time, so the constructor for ToolTips fails:

     // Create the ToolTip and associate with the Form container.
         ToolTip toolTip1 = new ToolTip(this.components);

--> found some sample code elsewhere and found that I needed to initialize "this.components" - not sure why yet (I'm new at C#) - would have expected the designer to do this:

     this.components = new System.ComponentModel.Container();