I am sorry, I must admit that I cannot find the KML Polygon Importer. Each link I try takes me at best to a comment or a blog post, but not to a download page. I would like to load the KML Census ZCTA files. I realize that the older ZCTA file for JMP was dated 2010, but even that seems to take me to blind searches.
On the display for the Addin URL, do you see the down arrow. The screen below is pointing at it.
If you don't see that, I suggest you try a different web browser, and see if that helps.
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