A lot of your questions can be answered by just watching one of the videos of instance runs in the sticky at the top of this subforum. That will show you how to position, when to pull, etc.

As far as your macro, personally I would not put ANYTHING in a castsequence that relies on runic power, as if you dont have it, you will then get stuck there forever.

The first 5 in your sequence are good - I would just leave those and take the rest off (it will automatically cycle through those 5 over and over again). I also use reset=target so if I switch targets it starts back at icy touch.

Other than that, you REALLY need to put 5 points in frost for toughness - it makes a huge difference. It also helps a TON to put 5 points in bladed armor (blood tree) because it will up your attack power by a large amount which will up your threat.