If your game is not starting, or you are receiving language related errors in-game, try backing up and replacing your specific language file in the game folder. Example:
Go to "\Steam\SteamApps\common\guardians of graxia\DATA\TEXT\" and copy the two ENGLISH.DAT files and rename it to your language.
Example case:
MASTERTEXTFILE_ENGLISH.DAT -> MASTERTEXTFILE_GERMAN.DAT
CREDITSTEXTFILE_ENGLISH.DAT -> CREDITSTEXTFILE_GERMAN.DAT
Run the game again and see if the problem goes away. We are looking into a more permanent fix, but until then this should help if you cannot get in the game.
If you have any questions, please visit the Steam forums for the discussion on this topic: