I haven't done this recovery myself, so I really don't know anything about it. I would suggest you to read through that topic and see if the answers are there.
The instructions do say "extract" and THEN "rename"
Some general things I can say though:
When burning an image to sd card the card doesn't need to be formatted before doing it.
To get the NT to boot from sd crad is individual from device to device. Many say they only get theirs to do it by inserting charging cable to power adapter.
The three that have passed through my hands have booted to sd either by themselves when turning on power. If they haven't done so right away I hold down the "n" and that's it.