There is no popup requesting a cd key. So can we be sure that is the problem? I don't mind fiddling with the registry, but I just want to make super sure before I go poking around in there.
Additionally, I did get into a regular multiplayer game in Crysis and played without issue (one server gave me the (3) error, the other let me in and it played fine.), however I still cannot connect to a MWLL server (all two! of them showing for me) because of the (3) error.
You keep mentioning Crysis Wars (I'm playing on Crysis), and I'm seeing that a lot here on the forums. I take it to understand that Wars is going to be the only supported game as of 0.5.0 and that Wars is the multiplayer component of Warhead, so if I bought Warhead I would also get Wars. Are those statements accurate? Do you find that more people play MWLL on Wars or vanilla Crysis?