okay, I can't figure out why the majority of my cities and the computer cities will not grow above population 6. Everytime anyones cities grow to 7, a immigrant is popped out and the size drops down to 6. There is no place for the immigrants to go and settle, so they just disappear. Very frustrating to be in 1734AD with lots of techs, lots of happy and health and I can't get a city size above 6. Ideas how to fix this, or do I need to wait for a bug fix?