Adding hunspell directories for spell checking does not work for majority of languages

Hi Ines-Paul,
as I learned from Daniel Naber (languageTool development lead) it is possible to add hunspell dictionaries to languagetool for languages, that languagetool itself does not support. Goal: simply use the hunspell dictionary for spell checking for those languages.
How this is possible I described at
https://confluence.translate5.net/display/TIU/Activate+additional+languages+for+spell+checking
because it so far is not documented somewhere for languagetool and we needed it for translate5.

Yet it turned out, that this works for some languages (for example for nb, nn, tr, be) but not for others (for example it does not work for bs, no, af, ar, bn, bo, cs, sr-cyrl, sr)

"Does not work" means, that you can start
https://bitbucket.org/mittagqi/hunspell-dictionaries-for-languagetool

This configuration is active on our server.

As I did check on marc.translate5.net, languagetool delivers all additional languages as active languages for the spell check with the API method getLanguages in our connector class.

Yet still for the listed languages the spell check is simply not active in translate5, while for other languages that have been added the same way (as Turkish) are working fine.

Could you please find out, if this is a translate5 bug (and fix it) or if it is a languageTool bug?

For reproduction you can use the task "Test für Ines-Paul" in marc.translate5.net

Thank you very much

Marc