Halfords cycle carrier damaged car - any similar experiences

My rack is a Hollywood rather than a Halfords but it was the user, not the rack at fault...

Stripped paint is likely caused by dirt under the contact pads. Did you clean the paint and pads before fitting the rack?

Indentations on boot are gonna happen unless you place the pads on load-bearing areas. I've found the most pressure is on the bottom pads of the rack though this is on a vertical tailgate. I place my rack with these pads on the bottom edge of the tailgate (after my first experience when I arrived to the campsite to find twin matching dents in the tailgate).

If you have a saloon car, try placing the pads just under the rear window and over the number plate. Both of these areas should be stronger. Look for where the weight of the bikes is meeting the car and see can you mitigate the pressure. Make sure the straps are tight. A moving load may have an easier time making dents.

Finally, check out 'no paint dent repair' for a reasonably cheap fix for the existing dents.