It looks some files may not have been overwritten on the installation.
We will be releasing an update to address an issue with the WA installer that we discovered last nigh later on this afternoon, that should correct the problem, or you can try renaming the configuration folder and reinstalling the extensions. see step 12 of the Adobe troubleshooting guide:
http://helpx.adobe.com/dreamweaver/kb/troubleshoot-javascript-errors-dreamweaver-cs4.html#main_user_config