It's as I expected. You can pair drivers up on a chart but with 34+ other cars running, it will be rare for a single pair to be competing directly against each other, and impossible for any pair to not be affected by the rest of the pack.
Then throw the yellow for safety reasons and look after the driver. If the rain starts, show some testicular fortitude and declare the race over. Easy frickin' peasy.
Yet another reason to drop GWC like a wormy apple.
I mentioned it during the race but the scoring pylon is the most basic, most necessary graphic. If you can't get that right, you have no business carrying races.