Under iOS 6 all my CCMenus appeared centered on the screen by default, if I did not assign an explicit position. Under iOS 7 the menus are positioned off screen
Basically there are two underlying problems.
If you have hidden your status bar under iOS 6, this will not work for iOS 7 without adding an additional value to your Info.plist (View controller-based status bar appearance -> NO)
Due to a bug in Cocos2D your screen size will be calculated wrong, if your status bar is visible.
You have to different options to solve this problem:
menu.position = ccp(self.contentSize.width/2, self.contentSize.height/2);
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