Interesting - I think you may have pinpointed the problem. Before removing it, I went through toggling everything on and off and when I toggled that one, it would swap textures around between two different arrangements (both wrong). I deleted it, and it still wasn’t correct until I hit play. Since then it’s been fine, but I’ll keep playing with it to see if anything else triggers the problem.
I have several other types of lights in the world, but none of them mess with textures at all when I toggle them.