Introducing the Library Guides
Shapes3D is a large and feature rich library and getting the most of it will take time and effort on your part, these guides are designed to help you.
My advice is start small with the basic shapes, Box, Cone and Ellipsoid. Run the examples that come with the library and then experiment by modifying the source code. This will help you understand what is happening and how it might be used in your own projects.
Before moving on to the more complex shapes make sure you understand the various draw modes and in particular how to apply textures and set the texture coordinates. These techniques apply to all the shapes in this library.
When you are ready to look at the mores complex shapes, Tube, Extrusion and Lathe Stock take each one in turn. The only real difference between them are the parameters used in their constructors.
As well as the examples and these guides you can also at the API references.