The behavior you experience is the expected one since when the ItemsPerPage property is set to 2, the topmost position is the one on the right - that is why when you click on the left item, it goes to that top position and the other item moves out of the view port.
What you can try is to set ItemsPerPage to 3, thus this topmost position will be placed in the center and none of the items will be hidden on a single click.
The other possible approach would be to leave ItemsPerPage set to 2 and set CanUserSelect property of RadCarousel to "False" In that way the carousel will not be scrolled at all on clicking on an item.
I am attaching a sample project illustrating both approaches.
Please take a look at it and let me know whether any of it is appropriate for you scenario.
All the best,
the Telerik team
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