Great job on all the fast and efficient bug fixes, guys!!!
Playing with a 2009 5 door hatchback, I noticed adding a front lip or a spoiler on the roof doesn't affect down-force at all. The Front and Rear sliders do nothing.
I was going to test it with another new car before posting this, so I started clicking through the build of a car in 2015 with the 2 door Charger style body, and the game error-ed and crash as soon as I tried to put on the front lip. Rebooted, tried again, it did work. Decided to make a HUGE V6 to see if encountered the problem of another poster of it being to long. The length arrow was yellow, but the 8.1 liter turbo V6 wasn't too long, just to tall. Raising the hood and adding a hood "lump" didn't help either. Shouldn't it? Anyways, using Throttle-body per cylinder fixed it. While tuning it, I reached the bottom end torque limit, but the indicators for that part stayed green, going straight to blinking as I added power, instead of gradually turning to yellow, orange, then red.
Anyways, got all the way through finishing that car, and the down force front/rear from lip and spoiler DID work.
So, I tried recreating a car quickly with the 5 door body style in 2009 again. Front/Rear downforce works! It's almost like the first one I made will not detect spoilers no matter what. I noticed the active spoiler button stopped working.
I've exported the car build with the issue and attached it. It's actually an attempt at recreating a 2009 Mazdaspeed 3. Now, when I try to add a front lip, I get a LUA error. Didn't do that when I started this post.
I hope this was helpful!