I downloaded the map and started playing. In the early game, I decided to develop Sigrif's companion instead of Sigrif himself, and it seems to be working well – on the sixth day, I captured the orange Underground City. That's all for now.
The only downside is that the computer still doesn't seem to be able to improve its logistics in any way. I'm focusing on developing Dark magic, as other types of magic are not very useful on large maps. Chaos magic is good for small maps and fast-paced battles with a relatively small number of creatures (the first few dozen creatures of level 7).
I'll let you know what happens next.