I do not think your problem has to do with any FreePBX module. The problem you have is because the FOP2 client (web application) is not able to connect to the fop2_server via port tcp/4445 on the server.
Only once the connection is done, you will be prompted for user/pass, etc.
You must double check if the fop2_server is running:
pgrep fop2
If it is, be sure it is binding to port tcp/4445
netstat -lnp | grep 4445
And finally, be sure to allow connections to that port if you use iptables or any other firewall anywhere between your desktop and the server. It could be a firewall in your desktop machine, it could be a network firewall/router, it could be firewall rules via iptables on the server.
