When I saw the new media labeled "Lower Thirds" I was hoping I could overlay an existing image on a content slide by using the "Add to foreground" option and it does. However, I can't put text in any of the fields. There seems to be two large text boxes on the slide, but only one place to enter any text. If I use the "apply to current item", I just replace my background image with a black background. Is there some trick I'm missing?