Update today to KDE 4.11.2 :)
I'll research more how others add folders in /home during the install, and have them in the correct language. They are now hard-coded in English when adding during the install.
I'll have to set up things in transifex (and figure out how to prepare all the needed projects for translations), the Installer needs to have all strings translated, than the home directories will be set in the correct language........