I met some issues with language in the exspansion, and those issues were related to a missing file that didnt appear, even reinstalling or checking file integrity. The string file was zpak100.p4, if some foreigners have issues with other languages, i suggest they look for a zpakfile with a different number in google, comunities upload them. I had to get it from a community forum that explained the whole bug.(location names were displayed with "str0000048" etc, same issue with weapons screens and elevator screens, in game computers,etc.
If someone from steam support is available i suggest they make a check on language string files.