You don't need the mod manager for custom scenarios at Nexus, such as Jericho and Exile, but it is needed for all mods.
With the limited game play capabilities of DoM, I'm thinking the small amount of buildable flat land is intentional.
The highest population count I've read about is 254 and the possibility of building a satellite settlement is minimal at best, since the people still wander back and forth between the 2 settlements when they could do whatever they need to do at one, if they're built right.
It doesn't matter if both settlements are built identical or not, they still roam back and forth between them to do their 'duties'.
Because of these current game limits, I honestly don't see much need for more flat land.
Don't get me wrong. I'd love to be proven wrong on the points I made.
Post edited May 14, 2019 by HawkDawg