At a loss with the listbox :(

[Zonx]

List box coloring is a nasty bit of nested styles and I think even a template file. 95% sure the colors you're attempting to change are coming from image art. You'll need to either change the DDS or change the references to point at some other image.

A little tip for yah... double-clicking a style ref in UIBuilder jumps you to that style def. Handy way to drill down this maze of nested styles till you get at the base object.