while some of the other plug-ins from same author (Fredo6), installed and loaded the same way, are fine. Mac OS Yosemite (10.10.5), Sketchup Make 2017. SU Restart doesn't help, nor Extension manager. Said plug-in doesn't show up with the others in the scroll down from "Tools" menu for Fredo6 collection. File is in its place, in the plug-ins folder.