Hi Joshua Ruppert,
Thank you for writing.
As far as I understand, you would like a different appearance from the default RadComboBox when the control is disabled (the Enabled property is set to false). Since in this state an image is drawn onto the control itself, you cannot change it.
However, thanks to the element hierarchy of our controls and the theming mechanism, you can change this behavior. You should implement your custom theme with added states to the necessary elements with condition when RadElement.Enabled property is set to false. Then all you have to do is to apply the theme and set the UseDefaultDisabledPaint property to false as shown below:
RadComboBox.ComboBoxElement.UseDefaultDisabledPaint = false;
If you need any further assistance, please write us again.
the Telerik team