This is a previously unknown, and so far inexplicable, error.
How many Plugins folders do you have set up ?
Do they all have .RB files in them ?
To find a list can you please do this:
Open SketchUp
Open Extensions > Developer > Ruby Console
Copy/paste this as one line:
puts "\nDefault:\n#{Sketchup.read_default("SCF", "DefaultPlugins", "???")}";lp=SCF_Dialog.getMyPluginsFolders();puts"\nAll:\n#{lp}\n\nContents:\n";lp.each{|p|puts Dir.entries(p).size-2 };puts"\nRBs:\n";lp.each{|p|rbs=[];Dir.entries(p).each{|f| rbs<<f if f=~/rb$/};p rbs.length};puts;
Press enter
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