Apply any font of any color, size and font decoration you need. Use any available type, color and thickness of a menu's frame. Choose any color for submenus and items backgrounds. Specify various values for spacing and padding for the whole menu and for each separate submenu. Create separators using your own pictures, size and alignment.
Save project. Save your image buttons as html You can save current project in the project file (*.xwb) or into the HTML file (*.html).
Click "Load image" and select the button image file you would like to add to the theme. It will be opened in the dialog.
Here are three state images in the example, so set total images" field value to 3.
To define the button's hot state appearance, set the "State offset" fields to 0, 1, and 2. Then the topmost state image will be set for the Normal state, next image - for the Hot state, and the last state image - for the Pressed state.
Press "Create button" button. Created gif buttons will be added to the current theme and will be opened in the Theme editor.