Hi Boz,
That´s my first post ^^d *yeah*
Every time you connect the Virus to the computer and load the plugin, the computer is getting the content of the RAM and ROM banks of the Virus.
It will not overwrite something. If you are unsure, use the Virus Control Panel to backup your patches.
I do this every time when I work on my patches and sounds to step back to the older version. ^^v