Sorry for bumping this after so long but I am currently building a simple peer-to-peer card game for a client for up to 5 players at once (using Auto-join for simplicity) and have run into this issue. I can't see any way for the host to set the room limit on the fly or to lock the game before the max players has been reached.
I really need the host to be able to set the game as locked or unlocked on the fly because:
-I don't want any extra players to be able to join once the host decides to start the game (game may not be full).
-My players don't want to spectate, they would rather join a free game instead.
-At the end of a game/round the host may want to allow players to join again.
If this can already be done I would appreciate it if someone could fill me in. If not, any chance of having this included in the next beta please Ashley?