Update a customized Ubuntu ISO file

We have a project for deploying servers and wifi hotspots for schools in rural places where internet access is not available. So, time ago we used this tool [login to view URL] to create this Ubuntu Customized ISO [login to view URL] and a set scripts that install the following software from a USB flash drive: * LAMP framework and php/MySQL custom applications * Moodle * PIWIK ([login to view URL]) * KIWIX (offline wikipedia However now we need for maintaining the project and adding more software like: [login to view URL] [login to view URL] [login to view URL] And make some adjustments to the original ISO like: * Make VLC default media player * Install and archive tool for compress/uncompress RAR files * Install SQUID (it is already installed but need to add authentication so we can track the behaviour of each user)