ISO 3166-1 Alpha 2 Country Codes
The most common problem you may encounter using this view is that the results for your mashable or mashup have country, region or continent names that do not match the ISO 3166-1 standards. One solution is to add ISO 3166-1 Alpha-2 country codes or valid country names to your results and use this field in the the view. You can find these country codes and names in English at
http://www.iso.org/iso/country_codes/iso_3166_code_lists.htm.
The easiest solution is to download these codes as an XML file (from the previous link) and register this XML file as a mashable information source. You can then use this mashable in mashups to add the specific ISO country codes to the results of other mashables or mashups.
This mashup uses the Join block to compare the country codes from the results of a mashable to the country names in the ISO county code data. ISO country names are fully capitalized, so it is usually better not to do case sensitive comparisons.