Hai there o/
I know there hasn't been much news posted lately about Zombie Co-Op, that's because I have completely restarted the mod due to it's lack of production value in the original 0.3 version.
Currently, the game supports Singleplayer only. I have focused more on the gameplay for now, and making sure it doesn't look slapped together.
Since it's in early development, if you see any lights, they have no sources. I am leaving the less-important stuff for last.
Expect to see a downloadable open-beta in the next few days, and new screens+video in the next 24 hours.