More than likely, its one of two things. Either, you have not closed your firewall (zone alaram doesn't seem to know about lfs, even if you tell it about it). Or, if you have a modem router, you have not setup the port forwarding in the router.
Both are pretty simple to do fortunately. For firewall, exit it
For Port Forwarding... then very simply, go here.
http://www.portforward.com/eng ... orwarding/routerindex.htm
Now; its quite simple really, pick your modem router from the list, on next page, pick Live for Speed game, then follow the instructions (ignore static IP), instead look up setting DMZ for your router.
Then it should work fine.
Easiest way to run a server is simply download Dedigui, just click the options you want ie track/cars etc n launch server... couldn't be easier.