fairly tight to fairly loose… and cloth just relaxes things so no good unless you make it very stiff and then it doesn’t crumple. You’d have to pre-make the form probably with Set Point Value (look for crumpled paper/tin(aluminium) foil threads/tutorials) then use Softbody dynamics to give it some spring when dropped. Though maybe some of the rounder forms could be faked with a soft body that’s been deflated (pressure)
expresso wants to calculate every frame, it might be possible but a python plugin that, given a material as input, generates a displacement (or just sets the seed) would be more what you’re after. Not that I know enough python to be a help…
the origin line for the extrude “P_slice_lg” has Intermediate Points set to Adaptive which limits the number of points along the long sides to as few as possible – in this case none between the corners – any other type will give you enough points to bend along the Spline, though Uniform or Subdivided will probably give you the best control without making too many useless points in the corners. it may help to give the Extrude a Regular Grid set of Caps if it’s going to twist at all.
The subject says change layer seed with xpresso but you are asking to change a material according to the seed. Which is the control? Put on a material and the displacement changes or change the displacement and the material changes? Or neither?
a C4D solution could be just add a disk and make it a child of the car so it goes where the car goes and then have a animated texture (an animated gradient would do) for the expanding rings.