The behavior is reproduced on my side as well. I have logged it in our feedback portal. You can track the progress on fixing it through the following link - http://feedback.telerik.com/Project/108/Feedback/Details/138555-prevent-choosing-a-color-in-colorpicker-to-trigger-the-dragging-of-rows-in-radgri
In the feedback item you can find a workaround script that you can put on your page and prevent the described behavior.
As a sign of gratitude for your help in this issue I have updated your Telerik points.
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