Depending on how you setup the UI code, it will "stretch" the image based on the coordinates you provide. It's definately not repeating the same image.
Here's an example from his code provided:
rect 0 0 100 100 // (these positions are relative to the initial position of the menu)
Let's do a breakdown of this. The first 0 represents the X value (which is 0 to 640), the top left of the screen is 0,0 (x,y). The second zero represents the Y (which is 0 to 480). The first 100 represents how far in width the image should be stretched, while the second 100 represents how far in height the image should be stretched. If you provide values less then the pixel details of the image, it gets shrunk... if you provide bigger values then the Width x Height of the image, then it gets stretched, not repeated.