by Philippe Decloitre.
This is not an anwser but a continuation...
I just stumbled on a very intesresting page (here) where I learned that what I took for NORMAL links were really transient links, that lead nowhere. No wonder backup does not work. It won't until the links include "pluginfile.php" instead of "draft" (that draft did look a bit suspicious..).
So to date we have:
No "true" link backup
No MyPrvFiles folder backup.
Am I right?
Thanks