because the gpo file in "sp3" and the gpo file (gameplayogbjects.con) in "coop/64" are of different sizes. When you run meuse river in singleplayer mode, there is no problem. but when run it in coop mode, yes crash happens. That means somthing is wrong in the gpo file in coop/64 . The gpo file in sp3 works fine. I couldn't find exactly what's wrong in the gpo file in coop one. but you can solve the problem by copying the gpo file from sp3 one into coop/64 folder.