property Background.ExtraPicture (Key as Variant) as LPicture
Indicates the layer's extra Picture object, so you can show any graphic on the layer's background.

TypeDescription
Key as Variant Any VARIANT expression that identify the extra-picture to be shown on the layer's background. 
LPicture A LPicture object that specifies the extra-picture to be shown on the layer's background.
The Layer's background can display unlimited graphics of different sizes and positions. The Picture / ExtraPicture property adds a picture on the layer's background. Use the Value property to specify a solid / EBN color to be applied on the layer's background.

The following properties can be used to move / resize the picture on the layer's background:

The following properties can be used to load / import ( manually or automatically ) pictures to the layer's background:

The PicturesPathPicturesName properties can be used to automatically loads files from a specified folder to be displayed on the layer's background.  

For instance, 

PicturesPath = "C:\Program Files\Exontrol\ExGauge\Sample\Design\Circular\Knob", defines default folder to load pictures from.
PicturesName = "`Layer` + str(value + 1) + `.png`", defines the name of the picture file to be loaded by the layer with the index / value. It defines the names as: Layer1.png for the layer with the index 0, Layer2.png for the layer with the index 1, Layer3.png for the layer with the index 2, and so on.

The Picture.Name / Picture.Value property of the Picture object loads a picture / graphics to be displayed on the layer's background. 

The Name / Value property could be one of the following: