TvLibrary.Interfaces\Epg\Languages.cs ( line 33 and 119 ) exposes two tables with full languages name and three letter code.

Those are used for example by Tvclient audio and subtitle section in MP configuration.exe


h4. Steps to Reproduce
Open configuration.exe and look at the list of languages. For example "Croatian" is missing.


h4. Additional Information
Full culture list can be retrieven from .NET with something like:

CultureInfo.GetCultures(System.Globalization.CultureTypes.AllCultures);"