Media Vault - Changing the Mirroring Mode

[murater]

I have recently bought a 2nd generation Media Vault (MV2120). I added the second hard drive as defined in the booklet as a non-mirrored disk and now it works perfectly.
My problem is this:
I want to revert back and add the second hard drive as a mirrored disk. No way!
In the software (Control Panel), in "Disks" tab, I only see the information about disks, but not the "add, edit, etc" buttons as defined in the User's Guide. There is nothinh I can change or edit the settings for the second hard drive.
I tried to take the second disk out of the MV, it gives an error and want me to re-insert it and it fixes the problem and gets back to non-mirrored state. No buttons or any alternatives to change it to mirrored state!
As I live out of the States, I cannot get support from US and I could not find any solution in any forums or support pages.
Can anybody give me an idea how to change the mirroring state of the second disk, or at least show me a way to do a hard reset so that MV reverts nack to its factory settings?
Thnak you..