Im playing with provence, im now in war with napoles but cant push the botton tu make the pu cause "he is on war with bizantium for his independence, u have to wait if he get it to claim the throne" or something like that, the funny thing is byzantium doesnt exist, and the war is against modavia, moscow, and other nations. when i start the war the option of the pu is available and bizantium already doesnt exists.