There's a new version 1.3 to download from here: http://www.xgn.com.au/index.php?topic=758.msg12369#msg12369This version uses the tyre dirt level as well to make the "wheels out" detection more accurate. This is what RSR Rank does. It's an improvement, but it's still not perfect, but it correlates pretty well with the RSR app. Even in RSR, you can drive completely off the track (e.g. off the left at T1 at Silverstone, staying on the tarmac), and be regarded as on track. This is because you're on a valid track surface, and because it's asphalt, it doesn't make your tyres dirty either. A limitation of the game. But it's better - it detects off-track excursions that it didn't before.
Copse at Silverstone is still a bit touch and go, because only that narrow green strip is off-track and dirty. The tarmac beyond that is clean and valid again. So you can still get lucky there and not get a cut, if you hit it just right. But sometimes it's a cut.
Thanks Marty for the tip to check out the RSR app.