Arrange Audio isn't doing what I think it is supposed to do - which is to to rename music files and then move them to a new folder within the designated root directory (which in this case is the same as the original location)

I'm using the following target directory / name string: [album artist]_[album]\[artist]-[album]-[track]-[title]
The original directory structure is: [album artist]\[album]
The desired directory structure is: [album artist]_[album]

Instead I get the following error messages for each file:
Error converting to [Arrange Audio], 'F:\Music_AAC_converted\Aerosmith\Big Ones\Aerosmith-Big Ones-02-Love in an Elevator.aac' to 'F:\Music_AAC_converted\Aerosmith\Big Ones\Aerosmith-Big Ones-02-Love in an Elevator.IGNORE'
Error Moving File 'F:\Music_AAC_converted\Aerosmith\Big Ones\Aerosmith-Big Ones-02-Love in an Elevator.aac' to 'F:\Music_AAC_converted\Aerosmith_Big Ones\Aerosmith-Big Ones-02-Love in an Elevator.aac

I'm running Reference 14.2, with the current version of Arrange Audio (At least Configuration doesn't tell me of an available update for Arrange Audio)
Moving the file with drag-and-drop in Windows Explorer works fine. Using the [origfilename] tag for the target file name produces the same error messages.

Any ideas?