I'm sorry, I've read this over and over and I still have no idea what I'm instructed to do.Here it is:

CCK File Field preprocess

If you would like to import nodes with CCK File Fields, you have to manually move the files at their final location before importing. This function will move your files to their final location before the import process.

This is how it works:

you have a node with a file field, which is stored in"files/nodefile" folder;
you copy your CSV file to "files/imports" (this is the default folder for node import module);
and you copy files to "files/imports/files/nodefile" folder;
when the new import file is found by ni_cron module, than all the files under "files/imports/files/nodefile" will be moved to "files/nodefile."

First, if I had a node already, why would I be importing? This is about nodes that don't yet exist, right?

What is this "final location"? For my regular Node Import (not via cron) I FTP my images to /sites/default/files/ and then run the import. Node Import finds the image there in the files directory, and imagecache copies the file into a half dozen places in files/imagecache/*, after it resizes them, but also the original file sits in files/imagecache/.

So are you saying I have to have two copies of the image before the import runs, one in files/ and the other in files/imagecache? Or do I have to create a copy of the file in files/nodefile and files/imports/files/nodefile as well? Or that I have to copy them only to files/import/files/nodefile so that the import can copy the file into files/nodefile? Do I have to have another copy of my imagecache directory inside files/import?

Node Import has always just looked in files/ and has never given me the option to upload images as part of the import. So what is going on?

I'm getting file copy errors on my import, so this seems to be the issue.