Big kart picture is definitely Autumn Ring Mini, the little ones could be course maker like Akira says.
Whilst there's nothing interesting to look at, it turns out we've seen this part in the new video, the course doesn't go down the centre road, it has split to the left of the high wall and comes back to the right of the solid white barrier. Since the trailer they've added high walls and adverts to replace the low barriers on the sliproad exit. I think that hints they've made the track reversable, not sure it needs to be really...
The weather trailer also shows the opposite end of the track, which does a 180 loop through a wide toll booth queuing area surrounded by floodlights. The game's intro shows cars entering and exiting that part.