I think you’re already running Windows 8 developer preview on your Computer system and also enjoying those lots of features with new Ribbon UI interface. Lot of users do not know about the Start Screen Editor while the recent release of Windows operating system has no functions to change the background of the Metro UI, it starts irritating the users.
May be it is possible in the beta version of the OS witch is going to be launched in the second half of February. You need not to wait until that time, there is a tool witch is called Start Screen Editor for your Windows 8, allowing you to change the green wallpaper behind the tiles in Windows 8.
The Start Screen Editor is very simple to use. You can modify the background panel either by plastering a custom image on it or changing its color. To get the rich resolution of the photos to cover the entire screen, you have to select PNG format at the time of applying the personalized images.
How to Customize or change background images and colors of Windows 8 Metro UI:
If you do no wish to add an image to the Metro Start Screen, then click Don’t use background image option. If you select a start screen image, make sure that it is in PNG format, and the height of the image is double the height of screen resolution to fill the entire screen. After you have selected desired options, click Patch.
Until the unveiling of the Windows 8 beta version of the OS, you can use Start Screen Editor to change the background of the Metro UI.
Download Windows 8 Start Screen Editor a Win 8 tweak that allows users to change the background image and color of Windows 8 Metro UI.