I did discover that the inability to generate a random map seems connected with trying to play it in 720p resolution. When I switched to 1080p, it didn't have any problem generating a map.
I put another several hours into it yesterday, along that line. (Tried to save it as a live YT broadcast for future reference, but the signal died without telling me about 5 minutes in.

) Still makes me want to look into the current state of
Genosia more, but it's fine. Don't believe the estimate for completing a road, though -- the code isn't actually programed to calculate that.
The supply-source limitations in the early game are interesting if just a tad hacky. I started with a "nomad" which is the basic unit, not terrible at combat, and able to build a settlement but that's all. (All units can build settlements in this game, btw, unless I misunderstood the rules, but the nomad and settler are better at it.) The nomad had both the "forager" and... um, rats I forget the other ability, pioneer maybe. Their descriptions sounded exactly the same for effect in different wording, so I couldn't figure out why there were two abilities: basically the unit doesn't take damage being outside supply. Okay, great, makes sense for nomads. I find a good settlement spot, the TEN THOUSAND NOMADS (unit sizes are weird in this game) found a settlement, and things move along. I create a settler (which sets off riots in my settlement, damaging it, because the settlers need TEN THOUSAND PEOPLE leaving over barely a few hundred at that point to regrow the settlement), and it doesn't have those abilities. This worries me, but turns out, nah, it has them but just doesn't say so. Okay.
Then I create a nomad to go scouting (once my settlement has bred back up to over ten thousand people), and I send it out to go look around because it can take care of itself better than the settler army which has no offense (but which can build roads and fields and clear woods to make fields later, etc., which is what I've been doing with it.)
The nomad army gets four squares north off past a lake into the woods and through a mountain pass, and starts to die. Because it's out of supply now.
...what? I thought nomads had those two (apparently equal) abilities to live off the land?! I happen to notice now that the two markers for those abilities are missing. They were given to the first nomad unit by the game to keep it alive until it founded a settlement. They aren't inherent abilities for nomads.
The ability to live off the land without dying, isn't an inherent ability for a nomad unit.
No doubt this is for game balancing. But still.

I did enjoy the extra 3 hours I put into the game yesterday. I don't feel I've gotten my money out of it yet, but I can see that's possible at least.