What do you mean, I have cores everywhere!
Please help me, I really can't play properly like this.
http://www.youtube.com/watch?v=fXwcsaK8AMI
I'll tell you what the most glaring problem is: you have 5 unused magistrates. You have a huge, cored, colonial empire, and none of the provinces you clicked on had even level one buildings. My general rule for easy building is: if you have four, build something (this way you don't lose fractional magistrates).
I have to run out. I'll add some more once I have a chance to see the whole vid.