Fiah, why did you make a bridge from the villager area in Spawntown to the main city? There was a reason why I made iron doors around the village area. :/
Anyway, I'll see how the population grows, because I expect that they might flood the main city. In that case we'll have to kill them off.
Also, there are a lot of places leading into the rails, where we wouldn't want them. They're not locked off by iron doors yet.
Remember the basic rule of regions: Ask the one who manages it before you make any significant change to the region. Making villagers populate a city is no exception to that.