I tried to find an exporter some time ago, and now again I'll probably need one for my project; but with everything I learned in this time about content pipelines (not only about the XNA content pipeline, I mean), I'm pretty sure I'll do an exporter myself - or an importer.
An importer (or content processor) is a feasible way to accomplish that because the only format the free version can export is KMZ, a zipped KML, which is just some sort of XML, very easy to be figured out.
On the other hand, additional exporters for the free version are not allowed, so even if you find one out there, you won't be able to install it. If I need to export something in a better fashion than KMZ does, I'll do it with a Ruby script, but I'm not sure yet if it's possible in the free version - it's possible to use Ruby scripts, but I don't know if they have some kind of restriction (no access to the filesystem, perhaps) that prevent the users to bypass this exporter's limitation.
So if you're not in a hurry and can't find another way to go (if you find, please let me know! :) ), send me an e-mail, and as soon as I have something useful, I'll tell you. I have a deadline by the end of March, so my solution to this problem must be ready in maybe one month, no more than two (no, I won't spend one or two months solving it!, :D it's just because until there I have a lot of other development to do in my project :) ). My e-mail is my screen name here in the forum, at the famous Google mail service (sorry, just to avoid spams).
