Shape libraries can be created using the ShapeDesigner tool that comes with MvcDiagram. Use the LoadFrom method to load a shape library from a file. The loaded shapes can be accessed through the Shapes property. They will be automatically added to the shared list of shapes kept in the Shape class, which lets you access them through the FromId method. A shape library can be saved into a file in XML based format using the SaveToXml method.

System.Object
    MindFusion.Diagramming.ShapeLibrary

ShapeLibrary Members
MindFusion.Diagramming Namespace