Well, you said that you have "no clue" what you're doing wrong, which is a somewhat ridiculous statement when your message includes an explicit error message telling you what you'd done wrong (specifically not having that file in the folder during the steps).
Did you keep a backed up bootpartition.bin as you were instructed? If you did, start from immediately AFTER the ipodfw -r N bootpartition.bin step, and try again from there, coming back here if you get any error messages. As you notice, you did get a reply not only the same day, but nearly an hour within your posting for your first post, and 2 and a half for your second.
You should always stop at an error message and research it, rather than just bullheading through. If you'd had a non-iPod MP3 player, there was the possibility of rendering it permanently unusable if you actually botched and install. Fortunately you're using one that has additional precautions built in, but we cannot protect against user error entirely, so error messages ARE there for a reason.