Sorry to have to rate with 1 star. I don't have problem with the interface/documentation. The 1-star rating is just to warn people that the data used by this module is not up to date. And that YEARS-old bugs are not being fixed.
At the time of this writing, this module still uses ISO 3166-2:1998 (first edition) + the newsletters (minor updates) up to 2006. When it should be updated to ISO 3166-2:2007 (second edition) + all the newsletters. For example, this module does not report 3 newer provinces in Indonesia.
Sadly we live in a world where countries and subcountries change all the time.