Release 10.1A: OpenEdge Development:
Progress Dynamics Basic Development

Adding and removing widgets

All widgets that you want to appear in any custom layout of the object must be part of the default layout, although they can be hidden. When working with custom layouts, you might delete and add widgets in AppBuilder. However, in reality, the widgets in the custom layouts are not added or deleted, they are simply made visible or hidden by your paste or delete actions.