@Javelin
It's in the menu
Tools > Fredo6 Collection...
It list all of the Fredo extensions that you have installed...
What Rich showed was ALL of his installed Fredo extensions.
If you don't have things installed they aren't listed.
If you have the Spline extensions, and also those in the collection bundle installed, then you should see those in that list...
You might need to restart SketchUp to sync everything...