I assume you are trying to directly access the files that make up the webapp.
Try running the webapp through the webserver on Mac OS X (Apache, installed by default). To turn on the webserver, open the System Pref. "Sharing" and turn on "Personal Web Sharing".
To do this, if it is just HTML files, move the files into one of the users's Sites folder. Then use the URL
http://<computer ip address>/~<username>/<filename>.html
Or put them in /Library/WebServer/Documents/
and use the URL:
http://<computer ip address>/<filename>.html
I've had trouble with scripts before and they work if run via the webserver.
Thank you.
Please choose accept if this is what you are looking for.