The Configure Sidebar dialog displays special add on control assemblies that allow you to extend your available library of controls.

Adding a new category is a two step process:

1.1. Press the New button to add a new Category.

2.2. Highlight the category just added, and press the Add Components button. This will pop up an additional dialog that will allow you to select a valid DLL assembly from the Global Assembly Cache (GAC), or from another location (Custom)