Hello,
I confirm the solution given by Aardvark Bellay.
The patch changed the default directory for CK2 user files. It also probably displayed the language selection screen again. Thats because the settings file is also located to this new location.
Just copy or move your saved games from one location to an other.
The new location (.paradoxinteractive) is a linux flavored folder for storing app files, the old one (Document/....) is Windows style.