As far as I know, there is no Arduino schematic or PCB layout done in KiCAD.
I've been meaning to give this a try, since it seems like it would be a good learning exercise for KiCAD, and I gave it a try after seeing your message. It was pretty painful. I was expecting kicad to be "odd" and "unintuitive" and "different than EAGLE", but I wasn't expecting it to be so awfully SLOW (kicad has its own cursor that seems to lag the actual mouse movement by about half a second, as the main annoyance.)