However, I tried a KMZGoogle Earth object, but Pepakura Designer wouldn’t even open it.The developer said that Google SketchUp version 6.0 or 7.0 worksbest. I also tried 3D Studio files and STL ...

The Pepakura download is free, unless you want to be able to change the scale of projects - in which case it's $30. Finding projects to make takes a bit of Google-fu; they're not all in one handy ...