based on our customers' projects most of the above listed languages are working. Following languages have not been verified or they are known as limited:
Indonesian - not verified, but it seems to use Latin alphabet. Probably working.
Thai - Limited. For example, the combination of multiple tone marks will not produce correct outputs.
Vietnamese - not verified, I can't answer whether it will work or not.
Mongolian - not verified, I can't answer whether it will work or not.
Please see also the section Language Management and Localization.