At the moment I have not a script to automatically create the live cd, but I will create it as soon as possible.
Now, if you want to remaster the live CD you have to install it on the HD with the procedure described in the post http://www.zeroshell.net/eng/forum/viewtopic.php?t=210 by fergon and then use the commands
mkzftree /source source.gz
(source.gz is not a file but a filesystem tree)
The isolinux directory is located in the live CD
Remember that you cannot use Zeroshell to use the above commands, but you should use another Linux distribution to mount the filesystem that contains Zeroshell.
In any case, when I will produce the 1.0.beta5 Live image, I will post more details about this procedure.