Raah, I want to play 4D1 for like the first time this week, but Steam is under maintenance? Can't connect to Steam servers. Is it just me or are more people having this problem?
The only way you will be able to play the game is by having it on Steam. If you buy MW2 in your local shop, or buy a key, you'll have to register it through steam. So 4D1 is a paid service. No excuses or exceptions.