Hmmm I just had a look at the save and the problem is not from your end Ramses, and your files are just fine.

What seems to be the problem is that econ messed up giving troops to the Hungarians. He seems to have given them "Dismounted Chivalric Knights" rather than "Dismounted E Chivalric Knights" as the eastern catholic factions have this extra letter in the unit variables.

It shouldn't be game breaking from what I can see (he made the same mistake in Outremer during the cataclysm with Turcopoles).