Well I did find out from Blender that Three.JS is arbitrarily altering the Spotlight center and rotation inexplicably. There is nothing in the code actually modulating any value, but for the spotlight specifically, it is getting garbage results in TG.
Both Blender support and myself with FBX SDK verified center and rotation in the FBXNodeTree:: , where it relates like it should. Three.js hasn't got back to me. They may not know either. Source seems to be just creating a spotlight with raw values. But their custom math tools may be the issue. I haven't looked into them.
But cameras and normal light sources work now with Euler order I mentioned elsewhere (can't think of it off top of my head) and 90 offset on Y.
I am not sure what to do about spot lights until I understand the problem better.
