do you still have that dust kind of thing going on? if it is its overspray meaning they painted something on the car and their mask job sucks. to get rid of it liquid cleaner wax and some elbow grease will do it. (i work in a body shop and have had to clean it)
do you think you could get me a picture of before and after? i can tell you if it has been done right. i had my bumpers off and i cant think of any gaps im glad you got it back tho. possible get a picture of the push ins in the trunk to bumper gap. if they arent stock then they jewed your insurance company and used some cheap one out of their stock to get more money.

 

I'll try to get an AFTER picture of the gaps, really not pleased with this. If you have an 07SS, it's this part:
BEFORE

 

I'm taking it back to have the body shop re-wash it. We are having freezing rain here today, and whatever's left of the powdery residue is turning chalky already.[sm=signs006.gif]

 

I don't think my car has a gap at this position? But then again it's not an SS.