That patch was released over a month ago, and has not caused this problem in general. So there's some problem in your installation.
Are you on Steam or GG? That is, did you apply the patch manually or did it happen automatically?
What version and checksum show on the main game menu?
Does this crash only happen with existing save games, or when you start a new game too?
Try this: manually delete the Documents CK2 folder (move any valued save games elsewhere first, of course) and let the game recreate it.