JanusVM uses open source software, but we didn't release the source because it was built with mostly .dpkg's.
You have root by default on the console (inside the VM) if you want to look into it or modify it to your needs. Option 7 in the menu will drop you to a shell.
Also, their will be an update in the up coming weeks for both JanusVM and Tor VM. Martin and I have both been busy with our day jobs and haven't had much time to keep these projects maintained.