Have you tried to use "Verify integrity of game cache"?
Edit: Can you upload the file here? You should find it in C:\Program Files (x86)\Steam\steamapps\common\crusader kings ii\interface
My current install of CK2 doesn't event include the file...
Edit: Can you upload the file here? You should find it in C:\Program Files (x86)\Steam\steamapps\common\crusader kings ii\interface
My current install of CK2 doesn't event include the file...