is that your router do the NAT or similar work ?
if that, you should:
1. edit the fcserver.xml , modify :
<server-address>*</server-address>
to : <server-address>192.168.1.100</server-address>
remember, the server address must using the lan ip , not the public ip x.y.z.w
2. add a rule in your router, you should redirect the tcp connection:
x.y.z.w port: 51127 (or other port) --> 192.168.1.100 port: 51127
if you don't use the 51127 port in your public ip, eg. n , you should edit the client.xml , <port value="n" />
3. edit the client.xml
if you use the domain name
www.yourhost.com ( point to x.y.z.w) to access the html file, eg.
http://www.yourhost.com/chat/aaa.html just change to
<host value="
www.yourhost.com " />
if you use the ip address to access the html file,eg.
http://x.y.z.w/chat/aaa.html
<host value="x.y.z.w" />
I just installed a server and integrated his mysql database for one customer, if you want , we can provide the service for you.