I am waiting for DT to allow for batch changing of pdf and rtf properties. In the meantime, I have had time to change my work from Sente to Bookends, and back to faultless BibDesk.
For the latter app, I have found a tool for setting metadata that is captured in BibDesk back into the PDF: pdfmeta. I post the link here because I think it hasn’t been posted in this forum before.
In this video it can be seen how it makes it possible to put DT properties’ columns to good use, as DT’s announced batch feature eventually would.