On my main app form, I have a TabControl.

I want to create an assembly that contains the TabPages, and then
programmitcally add those TabPages to the TabControl.  That's easy enough.
But what I can't figure out is how to use the designer to design the
TabPages.  I am adding a class derived from System.Windows.Forms.Form class.
I can use the designer to design that form, but I can't add that to the
TabControl, correct?  So, I manually changed it to
System.Windows.Forms.TabPage, but now the designer won't let me do anything
with it.  Well, I can add non-visual controls, but it doesn't give me a
display surface to add visual controls.  Any way to get this done?

Thanks!