OP, if you have any tuning experience at all the Datalogit software will be easy to figure out. I'm not sure if they still do it,but you use to be able to download the software for free to tinker around with it to see how it works.
Everyone that is concerned about the knock correction, but with the commander you can actually view your knock count. From the factory the PFC has a threshold that makes the "check engine" light flash if the knock count goes about the threshold.
One thing about the PFC tho..
It does not..I repeat It does NOT help control anything. It does exactly what you tell it to do. If you make an error it can cost you. The factory ECU will help you out by pulling timing if it detects to much knock.