Hi,
We do not speak 40 languages ; most of our language files are provide by the community.
If a language file is not up to date, it means that we didn't receive any update for the moment.
You can translate the file in your end and use the "share" button in order to share it with the rest of the community.
About the sys language file ; you can see to edit directly the "nl-NL.com_hikashop.sys.ini" file to force the new translations.
Regards,
Jerome - Obsidev.com
HikaMarket & HikaSerial developer / HikaShop core dev team.
Also helping the HikaShop support team when having some time or couldn't sleep.
By the way, do not send me private message, use the "contact us" form instead.