[reggoboy]

Thanks, Guy.

Curious, were you dealing with CSV-indexed PDFs, or just straight PDF files? 

The quote from the manual leaves me confused about whether the conflict is with the file names of the PDFs or with the song names. For indexed PDFs, like my situation here, those should be two different things. The business about putting PDFs in separate directories seems to suggest the issue is about file names. But the error messages I got clearly show different PDF file names, but a common song name. 

So perhaps this checkbox (and section of the manual) have nothing to do with the conflict I'm facing here......