In your browser, right click, and chose Import > File. Then select your JPEG file from your hard drive. Double click it to load it into the viewer. Set your desired duration. Move over to the motion tab. Adjust the scale as need be (to get your desired size). Then click on the + next to Center, the cross hair will be red on your canvas now, so you can drag the JPEG to whereever you wish. And voila, you now have your watermark in place.
