Similar (I think). I have a folder which I call "Mailbox". This is located on an external HD. Whenever I reinstall or reapply a new image, After reinstalling Live Mail, should it be needed, I go to File - Options - Mail - Advanced - Maintenance, and point to Mailbox as my storage folder.
This sets up my mail, exactly as was, all folders intact as before, and even finds and sets up my Email addresses.