We are using the german language pack provided by you as translated in Transifex on our site.
Since our upgrade to Joomla 3.7.3, the entire JomSocial component is only available in english.
You already detailed the changes necessary in your blog post (
These changes became necessary due to adjusted Joomla behaviour as detailed in the documentation wiki (
These changes were already implemented by the german language team on Transifex (and probably other languages as well).
However, the language packs linked on your download page contain translation strings exported in march, which do not contain those fixes and therefore will not load at all.
Please re-export or rebuild the Transifex translations and update the language packs accordingly.