The following link has a great example for Button FillPrimitive.
https://docs.telerik.com/devtools/winforms/telerik-presentation-framework/override-theme-settings-at-run-time
However, I am having a lot of trouble trying to do the same thing with my RadButton's BorderPrimitive.
The following does not work.
this.radButton1.ButtonElement.SetThemeValueOverride(Telerik.WinControls.Primitives.BorderPrimitive.ForeColorProperty,Color.Red, "", (Telerik.WinControls.Primitives.BorderPrimitive));
What will work? I tried accessing this.radButton1.ButtonElement.BorderElement but there is no SetThemeValueOverride member.