Ruined Hatch/Paint

[Chunkaway]

Hey all,
I have a quick question about my Space Blue 2006 Checkmate MCS. My wife and I recently drove to and from Portland, OR to Fargo, ND in our Mini. The car handled beautifully, was very comfortable and was a blast to drive!

So, my problem... Of course on a 3,000 mile trip the car is going to get dirty, get bugs on it, etc...No big surprise there. Well, I washed the car-hand wash at a "do-it-yourself" place- a couple of times on the trip. (I never saw any problems with the car or paint after these washings.) Anyway, there were a few days where the car was really dirty-covered with road grime, dirt, etc... and it was pretty hot-90 to100 degrees. I didn't think much of it....until I got back home.

I washed my baby and was shocked to see the back hatch, rear bumper, etc... was "stained" with dirt marks and streaks. I washed and waxed the car THREE times in an effort to get the marks off the car, but nothing has seemed to work. The rest of the car is absolutely fine, which makes no sense to me. It is the weirdest thing I have ever seen. The rear of the car looks like it is still dirty! Does anyone have any ideas? Fixes? Anything?

Thanks,
Paul