You're making it way too complicated, it's really simple.

On one computer, select a folder in Nautilus and right-click on it. Select
"sharing options." You might be prompted to install some software; if that
happens, install it and start over. A window will open called "Folder Sharing."
Click on "share this folder" and give it a name. Also click on "allow others..."
and "guest access." Click on "create share" and exit from Nautilus.

From another computer, open the "place" called "network." It's all double-click
from here, on my network I go to "Windows network," then the workgroup, then the
computer, then the share. Done.