I would also like to see the AI Mictlan mod. I find a dozen or so mentions of it but I cant seem to find the mod.
However, one of the comments I did find doesnt make me too eager anymore.
"I made an AI Mictlan in some random thread but no-one seemed to have any interest in it - it just gave them unlimited bloodslaves basically, since the AI is miserable at blood nations."
Heehee. Sounds like the kindof response I would get if I tried to mod a nation.
But it might be worth looking at. Maybe someone will come up with something better.