RACE 07 Online Problem

[Tom]

Myself and MazdaPrice have been trying to race each other online in RACE 07, we've both got the game on Steam and we can create lobbies sucessfully. However, we cannot join each others lobbies, and we're slightly unsure as to why this is. I've tried joining other lobbies and have again been unsucessful, we've tried, with passwords, without passwords, you name and we've tried it. Is there an option or something that prevents us from joining lobbies or something? As this is incredibly frustrating.

Thanks in advance,

Tom