Java error in wizard and CSS errors

Hi - Hope you can solve this one - I'm tearing my hair out!

(Running: iMac 3.06 GHz Intel Core Duo, OS X 10.5.8, Dreamweaver CS4 10.0.0 Build 4117)

I'm having major issues with Site Assist Extension 3.2.3. When creating a new site with it, I get a Javascript error when I try to rename the pages in the wizard (see java-error.jpg).

Also, when the site is created a lot of the CSS is not carried out. For example, if I specify the font as Arial, Helvetica, Sans serif - it displays a serf font (see finished_site.jpg). Also, the default images are not shown and I think the layout is wrong. The footer info also shows wrongly with 'undefined' after each link.

The path to the site is 'Macintosh HD/web sites/GH2'

I have uninstalled and re-installed the extensions many times, deleted the MacFileCache.dat file and re-installed numerous times and nothing seems to work. I've tried a previous carnation of Site Assist, but that too doesn't work at all. I've also reinstalled Dreamweaver.

For an extension to save time - it's turning into an extension to swallows time.