You can apply any count of KML files in one map. Use for it paths.
There are two place there you can call kml
- map details - only one file for map, it is for easy way to show
- paths - each path can contain kml file and show it
Read only google's restrictions for using kml (file size, and etc)
You can't design and create 3d polygons in my extension. I think it is not easy task. And my extension - only shows maps with its objects
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