Features / Usability

If you have a hardware firewall or router you will need to configure port forwarding for the port you using on apache normally port 80 or 443 for SSL.

I'm assuming your running the server. If you type http://localhost/ or http://localhost/tiki/ on the server computer and get tikiwiki to work then its just an apache network configuration error. You may have apache bound to only the localhost loopback address or to the wrong ethernet card (if you have more then one ethernet card or wireless).

Have you got it to work on the server using the localhost address?