By default, the Debug property is exNoDebugLayer. Use the Debug property to display the layers in debug mode. The ShowLayers property indicates the only layers to be shown on the control. The Debug property specifies debugging information to be shown while dragging the layers. Also, properties like OnDrag, LayerFromPoint are not valid while the control is running in debug mode. 

The following screen shot shows the control using pictures from the C:\Program Files\Exontrol\ExGauge\Sample\Design\Circular\Knob folder ( Debug property is exNoDebugLayer, default ): 

 

The following screen shot shows the control while Debug property is exDebugLayers: