https://imgur.com/a/wLI5yA4
How to fix these buggy projected lights for Redrock Ridge and Lost Canyons?
Is it a polygon setting?
I'd like to switch from vertexed to projected headlights because vertexed lights have annoying texture flickering on the side.
This is "projected lights" bug and propably not possible to solve, you just can reduce this problem. If polygons texture has transparency, all vertices conected to this polygon has still "vertex light" effect, like trees, guardrails, fences, road lines, lots of pillars, ...
EA used transparent texture on polygon which are not seen, if you change texture to something without transparency, "projected lights" should work fine.