How long did you wait until you gave up on limewire and quit the program?

It may take limewire some time to find good hosts to connect to. As long as limewire has not established a firm connection with at least one other host, you will see the red dot and it will say 'disconnected' in the title bar.

In order to check whether limewire actually is in fact searching for good hosts, check the 'connections' tab. If it says 'connecting' or 'handshaking', you should eventually connect. If there's nothing, you either unchecked the 'connect on startup' checkbox in the options or there's some other kind of problem.

In that case, it would help to know whether you are using a router or a firewall (is that what you were referring to when you said you 'disabled' security?).