At the conclusion of the sixth day of creation, God looked at everything He had made and pronounced it was "very good." Genesis 1:31.
This is intended as a brief thought on the issue of sin in God's creation. I'm not sure how firmly I will stand on all the following, but this is where I currently am in trying to pull together scripture and what I have heard and read recently from people like Greg Koukl, STR, and John Piper, Desiring God.
It seems most people have a very difficult time reconciling a loving and all-powerful God with sin. In fact, atheists throw it back at us all the time as a disproof of God -- which is no disproof at all but, rather, a very strong case for God's existence.
I know, I said brief, right?
OK. Here's the big thought: God created a perfect world - one perfect for His purpose. And His purpose is to manifest His Glory to the utmost. Creation is not for my comfort; it is for God's Glory! God is the point and period of creation.
You can waffle around all you want as to whether God created sin/evil, but you have to allow at the very least that God allowed it in His creation.
God is in control. "And we know God causes all things to work together for good to those who love God, to those who are called according to His purpose ..." Romans 8:28
We are created moral beings - we make choices between good/evil. It is in the struggle of good/evil and the overcoming of evil that God's Glory is manifested in us.
Evil/sin plays a role in God's plan. It hurts, and it destroys -- but it cannot destroy those whose faith is in God - those whom He has called to be conformed to the image of His son, Jesus Christ (Romans 8:29). Where sin abounds, there God's Grace (and His Glory - our right response to His Grace) even more abounds (Romans 5:20).
Yes, even sin plays a part in God's perfect creation.
We, the natural man, seek after emotionally satisfying answers. I think the emotionally satisfying answer is there but it is very hard to come to a point of comfort with. In fact, it takes a lot of faith and a willingness to rest our emotional satisfaction in God's sovereignty.