OK, with help from some kind folks on the SketchUp forum I think I have the problem solved. Just in case someone else has  this same problem here is the solution. The path C:UsersYOUR USERNAMEAppDataRoamingSketchUpSketchUp 2015SketchUpPlugins  was hidden by default on my computer.  That is obviously why I could not find the AppData folder and it's subfolders.  Someone suggested that I go to the properties for the C:UsersYOUR USERNAME folder and make the hidden files visible.  Then I copied the Vue Export ruby files into the Plugin folder and restarted Stetchup Make 2015 and the Vue Export is now available. Hope this helps someone else.