I've been trying to find a way of removing the faint silver bottom border that appears in TAdvMainMenu. I've tried every permutation of setting border colors in the menu styler to white, but this one border is always drawn. See the image below:
Did you try Styler.RootItem.Color = Styler.RootItem.ColorTo?
Yes, more or less (but I also just tried exactly what you suggested). In my case, both RootItem.Color and RootItem.ColorTo are clWhite. However, the line is still there. I think the line is clBtnFace, because if I make RootItem btnFace, and the panel adjoining the menu also btnFace, there is no sign of the line at all. While that sounds like a solution, I really don't want this area of my app to be clBtnFace if I can avoid it :-)
PS: I just wrote in my last post that I made the "panel adjoining the menu also clBtnFace". This is misleading. There is no adjoining panel: it's just the form background.