Help with Skin Builder

I am trying to create a new skin for my app using Skin Builder.... I am really having problems understanding how everything works and what each property does.

Is there any help documentation or tutorials for Skin Builder... I've searched code jock site and googled a bit trying to find something to help me design my skin but couldn't find any.

The current problem I'm facing is trying to understand how the SizingMargins work... I want to add some sort of shadow to the frame by drawing the shadow directly in the image and not by using the shadow properties of Skin Builder since I'm not sure how those work as I'm not seeing any changes when adding EdgeDkShadowColor, EdgeShadowColor or ShadowColor properties.

I'm really clueless here and not sure how one is supposed to use such a utility without any tutorials or a help document describing the ins and outs of each control and property.

Thanks