The reason that there is a lock symbol on the replica drive during a restore is that the drive is showing that it was not safely removed from the computer at some point.
To correct this condition so that you can restore the image that is on the drive run Windows Checkdisk with the option selected to fix problems that it finds.
Click here for instructions on how to run Checkdisk
At this point you should be able to boot to the replica CD and perform the image restore normally.
