To invite a friend to your game follow these quick steps;
- Open your Steam overlay while in CSN:Z (by default, by pressing both [SHIFT] and [TAB] at the same time)
- Right click on the friend in your Friends list you want to invite to your game room.
- Select "Invite to game" (Above the "Invite to chat"/"Invite to group"
If your friend was not currently playing CSN:Z when invited, accepting the invite will only launch CSN:Z for them and take them to the main menu.
If, instead, your friend had already CSN:Z running, they'll be automatically redirected to your same Server/Channel/Match upon accepting your invitation
To join a friend that is in a CSN:Z game room, right clicking on their name from your Steam friends list and select "Join game".