Hi
At which point are you stuck at ? I guess it is adding and removing users, as this requires setting the users password.
You also need to add the same users to the system first (on mine I did anyway).
There are better tutorials than this around, for a start I'd rather leave the keyboard and monitor plugged in (with gdm enabled) until everything is working and then setup remote access.
Try these....
https://help.ubuntu.com/community/SettingUpSamba
http://www.howtogeek.com/howto/ubunt...ver-on-ubuntu/
Take your time and you will have a fileserver is secure and never needs rebooting.
Regards
Stefan