A great app and I use with pleasure!
There is a small problem when you try to add the same favorite on different positions (in different maps in the favorites lists). The second (double) favorite has no tumbnail and comes with the error "error loading image". I use sometimes double favorites because I use one favorites map to view the images in the widget. You may only select the images from one favorites map, so I put these then in one map. This is also the reason that a favorite can exist more then one time in the favorites list (in more then one map).