Design a custom grid and use this as a background image of the script.
The best way would be to take a screen shot of the current grid first, and then edit the screenshot in your favourite editor, eg PhotoShop. You can edit the image however you like, eg. color the blocks, adding graphics, etc.
And then follow the tutorial for creating a background image here: http://www.milliondollarscript.com/installation/tutorials/alpha-blending-tutorial
You may also want to experiment with the setting opacity for the background image (eg. set it to 100%)
Once you have it ready, input the background image via the Admin and process your image to get the result.