I have restarted since the issue, no fix. I'll try again because hey why not. While waiting for a reply here, I started flipping mods on and off, trying to see if I could stumble upon a working setup. This, naturally, lead to CTD on start. Frustrated, I flipped off all mods and started fresh... and it worked! I reclaimed my animations (everyone had gone stiff and looked like levitating scarecrows), and FNIS compiled. I'm currently in the process of turning all my mods back on, one by one, and seeing what causes the issue. If I can pinpoint a culprit, I'll be sure to post it here.