the way that overbridge works on a mac means that you can end up with multiple midi device entries for one unit …
potentially there can be three drivers in Audio Midi Setup on e.g. an A4, one for USB MIDI one for OB mode and one when an Audio/USB Class Compliant mode is on
sometimes audio midi setup needs a spring clean so as to present the right devices (i.e. delete all those e.g. A4 entries and then connect the A4 and enable all three modes, then the entries will be freshly repopulated)
The point to mention this is to prioritise that the USB MIDI mode is teh one chosen on teh device and that this is set before starting Sysex Librarian - after that it should be fairly straightforward to back stuff up using ‘record many’ or ‘record single’