Unable to reproduce this. If I create a user control and then add a simple event:
public event EventHandler Foo;
Then compile the project, open a form, drag the user control to the form, then view the properties, select the events tab, the event is displayed.
The only thing I can think of is that there is a bug where the events tab is not shown until you click to another control in the form. This happens if the properties window is not visible when you select the user control.