You need to specify in MapTiler the URL where you will host the tiles,
as Google Earth Plugin needs absolute address for the KML file to load
it.
I see that this is a problematic step so I made an update in MapTiler
templates and in the next version it is going to detect the location
automatically via JavaScript, this problems should disappear then.
BTW Google Earth Plugin is not loading the KML files from the local
disk of your computer for the security reasons, therefore even with
the new version of the MapTiler you need to first upload the tree to
the web to be able to display the tiles in Google Earth API in the web
browser.
Best regards,
Klokan
P.S.
The source code of this feature is committed under the revision:
http://code.google.com/p/maptiler/source/detail?r=18
--
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