Just as it says, in-game, I can't use chat. I've checked the hotkey, and it still says 'enter' to chat. Thing is, 'enter' does nothing. I've tried to find others having his problem but with no luck.
Yeah, there is a bug with that. It's the keypad enter it's looking for, so that would be Command + Enter. However, it's easier to change the key to something simpler, like 'q'. See also https://forums.uberent.com/threads/chat-problems-mac.53759
