The number of rotator items you see on the screen is only dependent on the rotator and item size. The control will fit as many items as possible in the specified width and height. By default, the scrolling is done item by item - e.g. first you see items 1,2, and 3; then you see items 2,3, and 4; etc. If you wish to show items 1,2,3 and then 4,5,6 etc. you need to set the rotator mode to SlideShow. This way the rotator will scroll the whole viewport at once instead of item by item.
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