Go to your ...\DynamicResources\Config folder, and open up population.ini.
Remove all the current settings and then paste:
FOR POPULATION LIMIT OF 200:
MaxPopulation=200
PopulationEntry=0,20
PopulationEntry=2,30
PopulationEntry=4,40
PopulationEntry=10,50
PopulationEntry=20,70
PopulationEntry=40,90
PopulationEntry=60,110
PopulationEntry=80,130
PopulationEntry=100,150
PopulationEntry=120,160
PopulationEntry=140,170
PopulationEntry=160,180
PopulationEntry=180,200
PopulationEntry=200,200
FOR POPULATION LIMIT OF 500:
MaxPopulation=500
PopulationEntry=0,50
PopulationEntry=5,75
PopulationEntry=10,100
PopulationEntry=25,125
PopulationEntry=50,175
PopulationEntry=100,225
PopulationEntry=150,275
PopulationEntry=200,325
PopulationEntry=250,375
PopulationEntry=300,400
PopulationEntry=350,425
PopulationEntry=400,450
PopulationEntry=450,500
PopulationEntry=500,500