Some of the languages listed in Language Section properties and in the Customize > Language menu are placeholders for languages for which there are no current translation files. If you'd like to help make GedSite available in one of the languages listed, see the Translations page.
The Site Language pull-down menu controls the language of the site created by GedSite. The pull-down menu includes choices based on the set of language files included in Language folder(s). The program folder includes a Language subfolder, and you may add a Language subfolder under your GedSite folder. For information about customizing the languages used with GedSite, see the Translations page.
Site Language, described above, sets the language used when creating the site. The Customize > Language menu command chooses the language for the GedSite program itself.
Some genealogy programs support multiple "sentence languages", where facts/events/tags have sentence templates for multiple languages. When GedSite reads a data file that has sentences defined in multiple languages, it will use the Sentence Language property to determine which set of sentence templates to use.