Online version in offline mode

[Mikael Larsson]

A friend of mine has installed GTR E online, downloaded in Steam. Everything works fine except when he goes offline! The game starts to stutter and it's impossible to play. As soon as he plug in internet again it starts to work. Strange?!

Since the game isn't 100% supported by Vista I guess the problem is there? Or what??
I have no problem to run the game in offline mode...