I have exactly the same problem as @izabla94
In December, after the update, I also had an error occurring so I repaired the game but it switched the language to English (I used to play in Polish for YEARS) and that was the only language available to install the game in. Frustrating but fine, I can play in English since I didn't find a solution.
Now, after Feb 27th update, I also received a message about an error occurring and not being able to launch the game. I repaired it and launched it but it was in Czech. I don't speak Czech at all, therefore I can't play at all. I uninstalled it and installed it again, and then the error reoccurs. I repaired it again, and it launched in Czech AGAIN.
Please help