Hi,
The 4MLinux packages are called addons.
When you execute 'zk' in your terminal, you will see the following:
Usage:
zk addon.tar.xz (install 'addon.tar.xz')
zk directory (create addon inside 'directory')
zk update (update my 4MLinux)
The command:
will create a new addon from all files that are present in the /new directory. You must try it yourself to learn how it works.
4MLinux downloadable extensions (e.g. java) are available here:
ftp://dl.4mlinux.com/
Unfortunately, you won't be able to replace Java in 4MLinux. For security reasons 4MLinux checks your Java installation. If Java is outdated, 4MLinux will block it and force the update. Sorry.