You're right, making use of the existing open config areas would be nice as well. There's one issue though - they are designed for left side driving only, so in order to support right side driving too, the road markings and signs would need to be updated in the layout.
I've already got a simple traffic light system in place so I can put them into the layout.
I think I'll start with a single player local InSim app for now and maybe extend it to multiplayer later.
I wonder how it would look with a slower rate of adjustment. Now it seems a bit too quick especially around 0:03-0:04 during the transition into the shadow before the tunnel where it changes in just like 10 frames or so. I know it's never going to be a perfect representation of human vision in SDR mode anyway, but I feel like the changes in exposure could be a bit smoother/longer.
S1/S2/S3 is just about the cars & tracks nowadays, while the physics, graphics etc. are unrelated to that. Vehicle mods was a bigger thing introduced in 2021. I think the upcoming graphics update could be something "big" that you describe (dynamic day/night cycle, better graphics, overhauled tracks, 1000Hz physics etc.).
On the track selection screen, there are X and Y buttons next to the configuration names. Those represent the "open configuration" allowing drivers to drive around the entire track area.
Every layout file must start with the track code, e.g. BL4_something.lyt. BL4 means Blackwood Car Park. You can see the short track codes for all tracks here: https://en.lfsmanual.net/wiki/Category:Tracks
The DBL4 prefix is a mistake, it should probably be BL4_.
Now that the latest test patch provides ways to control AI cars via InSim, anyone can try and create better AI system as a challenge Although even Scawen said it's probably not suitable for creating competitive racing AI because of the input data delays and density necessary for quick reactions.
I'm wodnering, where did you find the download link in the end? It's quite surprising to me that you couldn't find the download link when there's a big button saying "FREE GAME DOWNLOAD" on the LFS home page, and a "DOWNLOADS" link as well.