I am trying to override the background theme colour for a CommandBarToggleButton (in default visual state ie untoggled). Below is what I have (but not working) - help appreciated!
CommandBarToggleButton button = new ...
button.SetThemeValueOverride(Telerik.WinControls.Primitives.FillPrimitive.BackColorProperty, Color.LightGreen, "", typeof(Telerik.WinControls.Primitives.FillPrimitive));
button.SetThemeValueOverride(Telerik.WinControls.Primitives.FillPrimitive.GradientStyleProperty, GradientStyles.Solid, "", typeof(Telerik.WinControls.Primitives.FillPrimitive));