The Q2 2013 SP1 version of the controls that you are using was released in July 2013. Note that Internet Explorer 11 was not yet released at that time. Because of this it is expected to observe some unexpected behavior when using the Q2 2013 SP1 release with IE11.
Try upgrading the controls to the latest release and see how the behavior changes. The Q2 2014 SP1 version is scheduled to be released in the upcoming days.
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