Hi. Today there is a new release with one feature, which you ask me - change opacity for overlays. I added in map types new radio field (opacity manage) in path for ground overlays new radio field (opacity manage) Now you can allow/disable ability to change opacity for a layer. in map details new control - Opacity control in map details new field for position of this control If you enable Opacity Control, and your map contains overlay (map type and/or ground image) you can see new control (slider), and if you change it's value the opacity of layers (with enabled "opacity manage" field) will change it's opacity. You have to remember: your browser have to support HTML5 Most of modern browsers support it.