The moving backgrounds you see are called "Parallax Backgrounds", which are easy to add in a map, provided your location's floor is primarily transparent. All you have to do is draw the object you intend to have in the background, then save the file as an 8-bit PNG (this can be done in Paint.NET and other programs) and put it in the Panorama folder. Once you're in the map editor, you must check the checkmark in the Background section to add a background, and then select your image. You can then make the image scroll with the "Auto Scroll" options.
Hope this helps.