How to use the "+" buttons to pick objects?

Since Corona Renderer 1.5 all functions that feature a "+" button (for picking scene nodes - e.g. including/excluding objects) have been updated with new functionality. As before, you can click on the "+" button, then click on objects that you want to be added to the list. However, you can now also select an object, or a selection of objects, and then click the "+" button to add them all at once, while right clicking the button gives the option to clear the selection.