You are the leader of the Egyptian Army. Crusaders are attacking your cities, the Byzantines have betraid you. Take revenge! March to Mekka and Medina, Destroy Constantinople!
From what I can see nobody is going to be able to play this campaign as the file is an .rar file, whatever that is, as opposed to anything recognisable. In the absence of any form of readme there is very little that can be done. One quick fix, one might think, would be to change things manually to a .cpn file in case that there had been a genuine error made but this does not work - nothing appears in the custom campaign window within the game save for two boxes and these obviously represent some form of error as nothing opens up!!