growth control is working a lot better now, but still fails in some situations. it failed twice so far:
1) city had just enough food in stock to to gain pop ( 30/30 ) , if left alone it would work fine ( growth control on). however, if I set it to enhance production it would go to stagnant, which means that growth control gets turned off. but when that happens, the city grows into unhappiness due to having enough food to do so.
2) when I switched to Conquest, for some reason 2 cities grew into unhappiness. I'm pretty sure it was the 2 cities that were building units.