Porteus

I have a requirement to change my Firefox User Agent frequently. I tried changing the prefs.js in the settings.xzm But the User Agent defined while building the Kiosk build overrides. Any idea what should I be doing? Should I create a seperate module say name userprefs.xzm and add my prefs.js in it?

Without this creating the entire build is cumbersome.

Any help on this is appreciated

Easiest would be enable remote management (with nested configurations if needed) and update remote config with a cron job running on your server.
Remote management works with PXE boot.

Remote Management is not possible in my case. I have a wierd scenario wherein the user machine must not have a default gateway in the NIC. I was hoping there would be a way to override it using the modules.

You can use 'run_command=' and sed command to edit $profile/prefs.js and change any text string you want it in.
Google for 'sed' usage examples.