FAQ 176 - different layer types
The User Layer is the layer in which all Layout-specific options, configured via the Customize area, are saved. A layer of this type will automatically be created for the user upon saving their Individual Customizations. Although User Layers can be created manually, they should not include functions or properties other than what is available in the Customize area. If you create a User Layer that contains additional properties or functions, this additional information will be lost the next time you customize your journal. Instead, you should use a Theme Layer for this type of customization.
FAQ 124 - what are overrides?
