AI-drivers need a .knw file for each car/track combination.
Without the files, they refuse to drive mod cars.

These files are in foler: LFS\data\knw
We can copy and rename an existing file.

Example:
We want to drive the mod car FORM07 at Blackwood.
1) We get the ID of this mod, for example from webpage list: https://www.lfs.net/files/vehmods/9A9019
It is 9A9019

2) We make a copy of an existing Blackwood-file, for example BL1_RAC.knw (Raceabout at Blackwood)

3) Rename the copy to BL1_9A9019.knw


I guess some people already knew this trick but maybe not everybody.
Of course it is an unofficial way and the AI performance may vary.

thanks a lot !!!
i don't know this trick.
it is always usefull to have dedicated topic for these kind of things

Thanks - I didn't know that yet.

doesn't work for me for some reason? oh well, i'm sure official ai support will come at some point.

It does work for me with the UZM 1700, and very well. But didn't work with others I tried: seems that as soon as I add the AI to the race, the knw file gets deleted, and then when starting the race LFS complains about mising knw file.

Quote from jaimevives :

It does work for me with the UZM 1700, and very well. But didn't work with others I tried: seems that as soon as I add the AI to the race, the knw file gets deleted, and then when starting the race LFS complains about mising knw file.

I had the same issue. it seems to depend on the mod.

Shame the editor doesn't automatically export KNW files.

Quote from jam_1989 :

Shame the editor doesn't automatically export KNW files.

Hopefully that will come soon.