Modding Settlement Growth Question

Hello, just wondering how to edit the population required to upgrade a settlement or castle.

:help:

Backup then open descr_settlement_mechanics.xml (drag it into a notepad), scroll down to the bottom of the file, edit the population levels, and close to save the file. Just be sure that the numbers match, i.e. that you set upgrade of the level and base of the next level the same, that max is not lower than the upgrade level, etc.