I have no clue if this is an issue with IR or just the Complimentary Shaders v4.7.1 I use, but as the title suggests, if you have the shaders enabled track is shaded/rendered differently based on the orientation in which it's been placed.
Without shaders the track shows up normally, and yes, I've made sure my normals are good.

Here's some more in-depth details:
Going West > East renders the track normally, but going East > West causes "backwards" shading (lit areas are dark, while the ones in shade have weird gloss on them)

Sometimes only certain sides render correctly while ohters don't
Going North > South shades the sides correctly, but no the ends; and going South > North shades the ends correctly, but not the sides

Same issues appear on angled tracks too
SW > NE shades fine, NE > SW does not

And NW > SE vs SE > NW shades only partially corrects

I have no clue if this even can be fixed, but any help/tips are appreciated.