if its based on open atv press the blue button on your remote and highlight Software Manager on the left, then move to the right and select Complete Backup.
Sorry, I'm not 100% sure, I have 3 mvi files in /etc/enigma which are backdrop.mvi, bootlogo.mvi and radio.mvi which are the three I've played with in the past, there are others in /usr/share and /usr/share/enigma2 but not sure if they are used.
You could use putty to connect to your box and type the following commands to find all the mvi files on your box and then download them to your computer and check out what each one is
cd /
find -lname *.mvi