Ok, I think I found whats wrong.

I have these three classes in one class file wrapped by a namespace and this namespace is being imported into the user control base.

The first class is the one (GradientPanel) that is inheriting the panel control and is where I am overridding the OnPaint event
to draw the gradient.

The second one (GradientStyle) is the one that has the 3 properties (DrawMode, PanelColor1, and PanelColor2). This one has the typeconverter (GradientStyleConverter) atribute.

The third one (GradientStyleConverter) is the one that inherits the ExpandableObjectConverter.


I think the first and second classes need to be in the same class and not separate?