Merci, beaucoup de gens font Navigatrix possible. Je espère que tout va bien avec vous et Gerard. Aussi étrange que cela puisse sembler, je voudrais revenir à Apataki Carenage passer plus de temps.
(For those who don't know,
Apitaki Carenage is the best DIY boatyard in the South Pacific) 
I am having a little trouble understanding what you want to do.
First off, on the LiveCD version of Navigatrix, the user is 
nx.  This user (
nx) does not require a password.  This requirement has been circumvented by 
/etc/sudoers.d/00navigatrix which instructs the system in specific instances to grant access without a password.  By default, as a security measure, the 
root password is not set (I'm told, technically it is set, but it is unknown to anyone/thing, alive or not alive.)
...but that doesn't really apply to you.
Setting passwords with 
sudo passwd is a straight forward process, if you have 
sudo access.  It is always the command followed by the user for whom you wish to change/set the password.  If no user is stated it will change the password of the current user logged in.
Quote:
moe@io:~$ sudo passwd root  <---to change/set the 'user' root's password
[sudo] password for moe:   <-- for the 'sudo' command in the line above
Enter new UNIX password: 
Retype new UNIX password: 
passwd: password updated successfully
moe@io:~$ sudo passwd 
Enter new UNIX password: 
Retype new UNIX password: 
passwd: password updated successfully
moe@io:~$ 
Ok, that is how you set/change the password for anyone on a system you have 
sudo privileges .
To log on to the system, either automagically, or with a password, is controlled by the Light Desktop Manager configuration file found at 
/etc/lightdm/lightdm.conf .  For auto-login, it looks like this
Quote:
[SeatDefaults]
autologin-guest=false
autologin-user=moe
autologin-user-timeout=0
autologin-session=lightdm-autologin
greeter-session=lightdm-gtk-greeter
greeter-setup-script=/usr/bin/numlockx on
user-session=Navigatrix
If I would want the system to ask for a password when it boots, you place a 
#, like this
Code:
# autologin-session=lightdm-autologin
Although not necessary, I place a space after the 
# for readability.
Adding a 
# to the beginning of any line and it become a "comment" and not something the system will use.  Essentially it is a comment to a human that could be used to improve, fix, or revert the code.  
This file can be modified via 
Code:
sudo medit /etc/lightdm/lightdm.conf
Save, and exit.
Was this close to what you wanted to know?