They are just temporary cars that don't cause a big lag when you're on track. You can assign a button to load cars while on track.
Thanks Coutie. I presume that is "Load Vehicles" in the Misc tab? Is that a relatively new addition or is it one I missed because of rarely going to the Misc tab?
watch out with that “load vehicle” button.... It caus a freeze big time when loading cars.... at least in my car
Thanks for the warning Rinussie. The idea behind the yellow brick is good, so I can easily wait till I get back to the garage for the skin to load.