Apple Motion 4 - Manual (Page 909)

To save a customized generator to the Library
1 To rename the modified generator, double-click the generator name in the Layers tab.
2 Type the new generator name, then press Return.
3 In the Library, navigate to the Generators category.
Note: You can also save the modified generator in another category, such as Favorites.
4 From the Layers tab, drag the modified generator to the Library stack.
909 Chapter 15 Working with Generators