Changing the color theme in UltraEdit / UEStudio is very easy. As of UltraEdit v20.00 (UEStudio v14.00), you can change the color scheme for the entire application by switching themes via the Themes group in the Layout tab. With traditional menus, and in the Mac / Linux versions, themes are located in the View menu.
Themes contain all color and font settings used within the main application area, and also control syntax highlighting colors. You can modify themes very easily or create your own via the Manage themes dialog.