Did you have a month of plague? I keep getting it stubbornly, even though I've rolled back and replayed from 141 in different ways. It feels like it's somehow hardcoded into the map and unavoidable. I'll try to continue with the plague.
Although I see that if you play with HD+, there's no plague (but that's unsportsmanlike, of course).
upd
No, it's fine, I went back to the beginning of the week, played carefully, and avoided the plague.
I always play with the SoD_SP add-on, so there's no month of plague. On this map, a month of plague, especially on 211, could probably lead to a loss! :)
More importantly, though, that creatures on respawn don't block critical landing/takeoff points, etc., which sometimes makes the map impassable.
I've already played up to month 6, and I'll likely complete the map.
I won't spoil anything, but at one point I got the Cloak of the Undead King from killing Galthran, I raised 20,000 liches, and the game became uninteresting. So I hid the liches in a far corner and play with a "normal" army.
There are a couple of mistakes on my part during the walkthrough, but I plan to describe them in a report after finishing.
One thing I can say: I already like the map!