OnClick events through a visible Widget

Hi guys and gals,

I am trying to implement a customizable game UI, using small widgets, that can be dragged and dropped on a MainWidget, going over the whole screen. It seems I have to set my MainWidget canvas visible to make it aware of drop operations. Problem is: when doing so all OnClick and OnCursorOver events of other actors in the level are blocked. Is there any way to solve this?

I hope my question is clear enough.