Grullert, I can help you with the advice Narelle gave, it’s rather simple.
With the game installed, open Steam (not in ‘Big Picture mode’) and go to your library, where the game is shown.
Rightclick the game and select Properties at the very end of the list. You get a new window.
Select the tab “Local Files” close to center of the tabs.
The fourth item down should be “Verify Integrity of Game Files”; click it. You get, yet again, a new window.
Now you get to watch grass grow, or fix lunch, while Steam compares what should be to what you have.
After a while, you will get one of two messages. Everything is OK, or X number of files did not validate and were replaced. There is no guarantee it will fix the problem, but at least you know your files are OK.
Close all those damn windows and try to start up CE to see if the problem still exists, and let us know, please.
Good luck !
Regards
jim