1. A system for displaying a layout for a graphical user interface properties panel, comprising: a computing device capable of executing object-oriented computer programs; a module comprising a GUI running on the computing device; a first section of object-oriented computer code defining a layout schema for the GUI, the schema comprising class definitions for a tabbed containment class and component classes, and relationships among the defined classes; and a second section of object-oriented computer code defining instances of classes for tabbed containment classes and component classes, wherein relationships between the GUI and layout of desired containments and components is modifiable in a text file.