Yes, once the wheel is plugged into the car's steering column/fanatec Wheel Base, the buttons light up regardless if the headlights are on or off as long there's power feeding into the wheel.
When it is in the car...
And when it is plugged into the Wheel Base (I feel this is pretty symbolic how the line is getting fuzzier):
Though there is an onboard where I assume the flash is used, the way they positioned the camera hides almost everything
I'm not sure where a pictogram/icon would be placed on the Bosch screen, whether it would be something like in the outgoing M6 or in the Audis and Ferraris and how it behaves, I don't know for sure yet until we get to see night onboard footages or reliable images. But for now, we have to wait for more media materials to arrive, OR, wait for ACC's version to come. 🤞
The exhaust and lights are some of the things I'm yet to see as well. For the former, we have not seen the car in action at night yet so I have no idea how it would behave at night.
Headlight flash is another thing I want to work on next in the config, the pit lights flash in an alternating fashion and I'm not sure if that can be done. It won't be soon because I have some work to get done. I'll try to do this on my spare time now.
There's only so much I can do. Besides, I'm not working with/for URD, and AFAIK, they said they're working on updates/fixes and I hope they would address these issues, I'm just providing my own input through this. Thank you for your understanding.