It seems that you're using an outdated browser. Some things may not work as they should (or don't work at all).
We suggest you upgrade newer and better browser like: Chrome, Firefox, Internet Explorer or Opera

Whenever I enter the game I never find anyone, neither in Cooperative or in Multiplayer, is it me, or does this version work badly or is there no one playing?
ive seen a few multiplayer games mainly team deathmatch but never seen anything for COOP maybe setup a lobby and sit in there for like 30 mins someone might join.