I kno that cso is a compressed iso, but would like to know what a ciso is and where do i put the ciso game file on my psp memory stick? I heard that ciso is a disc image or somethin and should just play like cso and iso. I have put a ciso on 2 my psp and it does not load on there! Could someone tell me where i put the ciso game file and if it is possible to compress a ciso to a cso or iso file plzz! Help hughley apreciated!