No put the following code into the HTML/CSS inserts:
HTML Code:
html{background:#XXXXXX;background-image:url('http://Path_To_Image/bg-bottom.jpg');background-repeat:repeat-x;background-position:left bottom;}
You of course would add the correct color code and path to the image.
What you have is one background image in the body set to repeat-x and positioned at the top and another in the HTML/CSS inserts