in the CSSMenuWriter/cssmw/menu.css file all the background image references use File System links:
background-image: url("file:///C|/Documents and Settings/John Ryan/My Documents/Dreamweaver2009/Quality Landscape ul#cssmwtenance/CSSMenuWriter/cssmw_images/left.gif");
they should be relative links:
background-image: url("/CSSMenuWriter/cssmw_images/left.gif");
Dreamweaver is supposed to update those paths when the menu is saved.