Here's a workaround that might work for you: Download Vitrite (2000/XP only), a tiny utility that allows you to manually adjust the level of transparency for almost any visible window. Open your Background image in a viewer and have Moi on top of it. For some reason with MoI you need to set a transparency for both the Image and Moi itself. Obviously you will need to keep your zoom setting constant while tracing the image.