qubodup: I'm sorry, but I think you have fallen victim to one of the complications of a work-in-progress game like this. The icon that appears unlicensed is actually just a temporary image that was duplicated from another icon (defense.png) until we get a proper replacement.
Would you be willing to make us a new icon? We need a 16x16 icon in a similar style, that represents a very large carrier UFO that is orbiting the planet. Perhaps a traditional disc UFO would work well for an icon? If you have other ideas that's good, but with 16x16 there's not a lot to work with.
Thanks again for helping out.