Data Bridge no longer has Client side validation, it uses spry validation that is included with Dreamweaver for Client side validaiton.
for the other issues, i think the configuration folder became corrupted. use step 12 of the adobe troubleshooting guide to recreate the configuration folder:
http://helpx.adobe.com/dreamweaver/kb/troubleshoot-javascript-errors-dreamweaver-cs4.html#main_user_config
then reinstall Data Bridge.