In MDID, there are few personal settings that you can manipulate at the user level. If you go under 'My MDID' in the left-hand column, there is a choice for 'Options'. Here you can set a number of different things, including where your images show up in the Light table when you create or add images to a presentation. The default setting is set so that when creating a brand new slideshow, the images show up in the Light table's presentation area (the main area). When adding additional images to a show, they then go to the scratch area (left-hand column in Light table). You can change the settings so that all images either go to the presentation area or to the scratch area. Your choice!