Update: I tried to add the same compressed iso to my HD with Vista and WBFS mgr... again, no dice. So I am guessing that the files are corrupt, or that because they are pre-scrubbed (end up with 678MB files instead of 4.38GB) once un-rar'ed, they are unable to be loaded with WBFS Mgr.
Is this true? Is there another program that can add them to either the WBFS drive, or even to an NTSC or FAT32 drive? I have several partitions on two HD's, and could re-format if needed. Sorry if this is an obvious question - I have been focusing on Mac answers, but will reluctantly start searching for Vista answers now, too, I guess...