Oh, weird, it won't surprise me if devs were working onto a snowy map, it seems like it was needed, just weird it wasn't announced, even though the ETK driving thing wasn't announced either. So, do you remember what dev showed you that and why?
I think it was around the time of the race update that video was shown, I asked the dev about the audio file and he showed me this video. I can't remember what dev it was.
I'm surprised no one mentionned the Hopper easter egg yet. I don't know if the "Classic" version of the Hopper can be considered as an easter egg too. I'm sorry for digging this thread.
The word "Knallhart" means tough in German. (Google translate, bro!) Also, the Knallhart is one of the models in the ETK I Series.
The Hopper's radiator fan is animated. While driving, it turns on periodically. Not to mention but half of the blades on it are crooked. This caught me off guard while driving with the bonnet off. I think the other cars have this, too.
Multiple multiplayer references can be found in the game file, like a lua file that sends nodestream via (udp/tcp? can't remember wich one), don't get too hyped.
De-tuned from just above 900, regulations changed that when they cut down on the downforce a few years back.