I don’t know why this worked but I deleted the modules folder it had Rhino 3dm in it, then after deleting I was able to check the check for your plugin and it worked. I think uninstalling the older plugin didn’t work for me and it left this older module folder? A new module folder was created but nothing is in it. I was able to import a rhino file and 3dm is on the import file list.
Thanks for your reply and for the plugin.
RM