[Cin] Does menu "Window' worksfor hiding/disabling windows for you?

Sorry, not sure if this is local issue or something like real bug (so late again ...) I started Cin even with english language, and still I only can, say, toggle 'Show viewer' window ON via this menu, but can not hide it again by clicking on same menu item again. I can hide/activate 'Show overlays' window, but apparently this is only one reacting this way ...