I've been assuming that LW is able to detect your IP, and then force it...as far as I know this deals with 2 issues...2 users being firewalled, and networks...I know that on Direct Connect, two users that are passive cannot connect...and this is basically the two users both being behind firewalls...it is dealt with by manually entering in one's IP address, and forcing it...by doing this, a firewalled user can now connect to any other user, barring of course issues like hacked clients and such..

I know that I have had no problems running LW in the force IP mode, and perhaps am having a better time at making connections..