This might also be helpful. The instructions for implementing a new theme from the user guide.
Place the main .css file of the theme into the
AwareIMRoot/Tomcat/webapps/AwareIM/ext20/resources/css directory
(where AwareIMRoot is the root directory of your Aware IM installation)
Place all the images of the theme into the theme specific folder
AwareIMRoot/Tomcat/webapps/AwareIM/ext20/resources/images/myth
eme
Modify the file theme.props located in the AwareIMRoot/bin directory to add the
new theme-specific entry starting with the prefix “Theme”:
ThemeMy=My Theme;ext20/resources/css/xtheme-my.css
The name of the entry should start with the prefix “Theme” followed by any unique
identifier. The value of the entry should start with the name of the theme as it will
appear in the Configuration Tool (My Theme), followed by the semi-colon and then
followed by the relative path to theme-specific CSS file.
After you re-start Aware IM the name of your theme will become available in the
Themes dropdown in the Configuration Tool. The theme will also become available
to the end users if you have a “Theme Selection” command enabled in your
application