I've spent several hours trying to figure this out. I have a programmatic skin that paints a gradient and sets it as a backgroundImage ClassReference in css. In that same stylesheet declaration I set the borderSkin to a ClassReference of a class that extends border and draws a line. A canvas is referencing the declaration. I'm confused because if I only use the background image style it draws the gradient. If I add the border skin style, it won't draw the gradient but draws the lines in the border skin. The interesting part is if I set breakpoints, I never even hit the breakpoint in the updateDisplayList method for my background image class, only the border class, so all I ever get is a line. Does the borderskin in css override other skins like backgroundImage? Are there documents that explain this somewhere on adobe's site?