You are trying to do too much at once. First only add a province, if that works add an army. Your fault may very well be caused by the new army.
When adding a province:
- split province with new unique RGB colour, add a city (port is not necessary so do not bother). Make sure that the city is not on a river, mountain range, etc.
- add the province entries (be it names, cities, population, etc) in the same format as existing provinces in (assuming that you are editing a "provincial campaign"):
That is all for the first run! Do not bother with assigning it to a faction, if you do you are trying too much at once and you're just asking for an unexplainable CTD. If it works then you can start on fleshing it out; resources, owner, mercenaries, techtree development. And do it all one thing at a time.
- \Data\Text\CAMPAIGNNAME_regions_and_settlement_names.txt
- \Data\world\maps\campaign\CAMPAIGNNAME\descr_regions_and_settlement_name_lookup.txt
- \Data\world\maps\campaign\CAMPAIGNNAME\descr_regions.txt
Use the correct new RGB colour.
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