My Cordoba campaign was crashing around turn 24 due to Frankish separatists taking a minor faction's settlement. I finally got it fixed, and here's how I did it:
I downloaded SaveParser, (https://sourceforge.net/projects/saveparser/)
put the correct paths in the .ini using Notepad,
copied the offending save,
loaded it into SaveParser,
located the Frankish Separatists (44), and reduced their strength in the Edit section
File>SaveAs over the old save
Tell me how all of your fare.