GRID 2 is an arcade racer. It has some level of simulation, but mostly it is targeted for regular gamers. Still, driving a racing car with a typewriter doesn't really sound sensible to me and I whipped up my G29 wheel and started the game.
Second: The XML-file everybody is talking about is here: lg_g27.xml. Place it into steamapps\common\grid 2\input\ (suggest backing up the original file first!) and then selecting Direct Input Device from game controller options. This enables choosing of Preset<lg_g29> and further tailoring controller settings to your own liking.
Had the same problem Tried the xml and it worked partially. All seemed well. But the handbrake seemed stuck, and I had no way to drive away.
However! Logitech G hub is their new software. Works like a charm!