I have the same problem as well. I don’t even get to get more than 1 percent going downhill. I get the limited regen warning which I have not experience with my other ev.
If overheating is the issue I hope they can fix it. Mine shows up in less than .5 miles going down a steep road even at 40 percent SOC. I never had this problem with my tesla or chevy volt which has a smaller battery.