I have and use this plugin http://www.alexschreyer.net/projects/plugin-loader-for-sketchup/.
I use the following Plugin folder layouts.
Plugin – This is where I store every plugin that I want to run automatically.
Also I have plugin in this directory that I wish for the Plugin-loader to install and not be loaded automatically. These plugins, I remove the file type .rb, just leaving the file name as “GetLines” not “Getlines.rb.” This way, the plugin remains in the plugin folder, but will not be loaded autmatically. But will load with the plugin-loader, because "plugin-loader" adds the file extension, “.rb”.
And the plugins that I wish to be loaded by the “plugin-loader” that I have chosen to remain in the plugin folder, I will remane by adding a number the front to the name, such as “1 – Getline.rb”. This will put the plugin at the top of the plugin in folder so I don’t have to hunt for it down in the directory.
Other plugins I move to one of the following directories below, selecting it from the “plugin-loader“ when I wish to run the plugin. Works like a charm.
Another thing I do, is I rename the plugin, i.e. Getline.rb may be renamed “To Get All Loose Lines– Getline.rb”. Note, I usually have the original name after the “-“ so I always know what the original plugin name was for future reference.
I do this reference annotation renaming so I have some hint of exactly what the plugin does. I have not found a plugin that would not run from plugin-loader that I have rename by this method.
My directory loayout, and I am thanking Didier Bur for the layout from his web page.
000 Steel Beams Angle
001 Animation – Scenes – Camera
002 Architecuture
003 Geometry – Drawing
004 Editing
005 Material – Colors – Rendering
006 Selection – Layers
007 Survey - Terrain Contour
008 Text
009 Files – Import – Export
010 Google Earth
011 Misc
012 Zip – Zar – Scripts
013 Script TXT Files
014 Data Files for Script Testing
015 Plugin exe Install files
016 Script Tutorials
Hopes this helps. I know it cleaned up my drop drown plugins list.
Ken