Replying for others information after talking to him in PM:
From the steam subsystem, how it generates its lobby settings:
/**
* Generate the proper lobby type from session settings
* @return type of lobby to generate, defaulting to private if not advertising and public otherwise
*/
if (bShouldAdvertise)
{
if (bAllowJoinViaPresenceFriendsOnly)
{
// Presence implies invites allowed
return k_ELobbyTypeFriendsOnly;
}
else if (bAllowInvites && !bAllowJoinViaPresence)
{
// Invite Only
return k_ELobbyTypePrivate;
}
else //bAllowJoinViaPresence
{
// Otherwise public
return k_ELobbyTypePublic;
}
}