Hi Daniel,
Just little question. I just tried your plugin inside R20Demo and don´t know if it´s c4d demo restriction or by plugin, but when I follow your steps, with moving mouse over mesh for copy there is not full line over edge and when click Ctrl and left click, I see transparent line over mesh for copy, but another selections for paste are deselected...
And mesage from console
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PolyDup - failed to extract the part of the mesh
PolyDup - failed to write the extract file: D:\CG2\MAXON R20 Demo\plugins\PolyDup\Extracts\extract.c4d
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Ahh, now I see...
Since it´s demo of c4d, there´s not allowed to write to any file, Ok, solved...
I´ll try in commercial R20 version, but just another question. Is posible to rotate copied mesh to destination place? Or there is some rule for placing copied mesh?