That is one awesome service. Didn't know that it is still working. I just gave it a try and scanned my area, and it found out all the information about the surrounding gym in my locality within 80 seconds.
It is a powerful web-based Gym Scanner. Thanks for sharing
And for your "map data not available" issue, I guess it is related to the Map source. Try searching for the country instead of the city, then manually scroll to your area, and then scan. It should work.