In the standalone report designer, when I copy and paste a group of adjacent TextBoxes, overlap warning icons appear on some of the pasted items.  I then tried moving the group of pasted items to a new snap-to-grid location, but the icons do not go away.  This can create a good deal of work to clear up the warnings by individually adjusting the affected items.

In the attached report, the three items in the report header are the original TextBoxes without overlap.  The three in the detail section are the cut and paste items showing overlap warnings.    The three in the page footer section are the cut and paste and move items still showing overlap warnings.

After submitting this as a support ticket, I received this message from Telerik: "The development team found an issue in the Copy/Paste logic and updated it. The change will be available in the next internal build for tests."  I was using 2017 R2, version 11.1 17.614.