Hi Burr - moving the folder over should not make any difference for this. MoI's installer basically just copies files into the folder, the only thing that I can really think of that the installer does in addition to just copying files is to set up an uninstall entry in the control panel and also setting up a file association for .3DM files if not already set, so you can open MoI by double-clicking a file in the windows explorer.

My only guess is that maybe you're running a 64-bit oleview which may not want to load 32-bit files. You could try installing this older version of oleview and see if it will work:
http://www.microsoft.com/downloads/en/details.aspx?FamilyID=5233b70d-d9b2-4cb5-aeb6-45664be858b6&displaylang=en

But you can also just download the moi.idl file from the link on that scripting page in the wiki instead of using oleview at all.

- Michael