Here's the state of my empire in my current game of CK, in which I started as Count of Usora (Croatia) and now hold the titles of king of Jerusalem and Syria:
Iberian Peninsula:
Balkans:
Middle East:
King/Kingdom details:
At some point, some muslims from Spain managed to take 2 provinces from the king of Croatia. Later on, I conquered those, along with my current holdings in Spain.
Because I created my own kingdom instead of breaking free, the king of Croatia doesn't mind too much the fact that I kept a few provinces, so we have relatively good relations. It won't last forever
He currently holds the title of king of Serbia on which I have a claim.
It is somewhat funny how I got my kingdom. It started with the usual crusade to liberate Jerusalem. After I successfully conquered the province, and a few neighboring ones, I had an event to give back Jerusalem to the church or whatever, which created the kingdom of Jerusalem (and gave me a whole lot of piety and 250 prestige). After a quick look at my new neighbor, I realized I could claim his king title for... 250 prestige
Guess what I did
When I got my kingdom, the Turks were all over the place: from Kuwait to Byzantion, from Acre to the very borders of the Rus empire. After the death of one of their previous leader, I did all I could to destroy them. Assassinated their new leader (a merely average leader) and got him replaced by a 1 year old child, assassinated the chancellor to screw his diplomacy and then declared war. I started the war with close to 5,000 gold and finished with over 15,000; after some of the Turks vassals declared war only to plead for a peace agreement, many offering tribute of 500 or so (one offered over 5,000). I gained almost nothing from this first war (Acre, Tiberias, Palmyra and Byzantion) considering I had to use every single men I had, including my vassals' and had to fight from Turkey to Iran and from Georgia to Jordania against an enemy that started with nearly 200,000 troops under his command... and had to deal with a backstabbing Byzantium empire at the same time (they only wanted Antiocheia however). However, I achieved to break the Turkish empire, they were left with nearly nothing except a bunch of rebellious vassals and ex-vassals.
My kingdom is in a relatively stable state at this point. My previous ruler died recently, so I am currently trying to make sure the succession goes well. I have 2 main issues right now. My kingdom is so spread out that it is becoming troublesome to deal with rebellious vassals, so I am planning to give every province in the Iberian peninsula to my vassal there who is a cousin or something. If he breaks free later on, I'll just let him go and hope he can create a new kingdom for our dynasty
If he declares war, I would just let him waste his time moving troops all over the world and offer white peace once his troops have been slaughtered. My second issue is much more annoying. The kingdom of Croatia, the Byzantium Empire, the Kingdom of Georgia (held by muslims) and the Turks all have claims on part of my kingdom. While none of them is strong enough to attack me on their own, I would have a hard time fighting any 2 of these at the same time. This is the reason I am currently allied with the BE. I will need to move against one of them before long or risk having them move against me.
Edit: I decided to continue the game after leaving it on hold for a week. A few months only after the above screenshots, the BE decided to do a bit more backstabbing. I mobilized every troops between Croatia and Syria, pillaging every byzantine provinces on the way before the damn fool agreed to drop his claim on Byzantion. I had a few claims on some of his provinces, but I dropped them all so I wouldn't have to worry too much about more backstabbing. Next step will probably be to force a war with Croatia so I can later focus on the eastern front without worry.