Javascript error at ThemeIt launch

Hello,
I am having problems getting ThemeIt to run.
I have installed and activated it.
With a new html page consisting of one coloured word and cursor focus within the page design view, I use the main menu to open ThemeIt. (Insert => Webassist => ThemeIt)
The themeIt interface opens, but with nothing in the left panel.
At this moment a javascript alert appears with the text;
"While executing onLoad in wa_managetheme.htm a JavaScript error occurred." (see attachment 1.jpg)
When the "OK" button is clicked, an identical JavaScript alert appears.
When "OK" is clicked the second alert disappears and the themeIt interface remains, but with nothing in the left panel.
If either left panel tab ("Manage Colors", "Manage Images"), or the "Preview" tab in the right panel is clicked a new JavaScript alert appears, with the text;
"While executing onMouseUp in wa_managetheme.htm a JavaScript error occurred."
When the "OK" button is clicked, an identical JavaScript alert appears.
When "OK" is clicked the second alert disappears and the themeIt interface remains, but with nothing in the left panel.
The Color Importer appears to be working correctly. It will display either a local html page or the webassist.com homepage.
When the ThemeIt window is closed, a JavaScript alert appears with the text;
"While executing timer in wa_themeit.htm the following error(s) occurred.
at line 127 of the file C:\Program Files (x86)\Adobe\Adobe Dreamweaver CS3\configuration\Floaters\wa_themeit.js: TypeError: MM.updatedImages[image].imageProps has no properties." (see attachment 2.jpg)
On inspection the file wa_themeit.js does not exist in that location. (see attachment 3.jpg)
System:
Vista 64 bit
Dreamweaver CS3
Most webassist extensions installed, plus 4 or 5 non webassist extensions.