I do not see where Librarian shows anything more than Performances (not individual parts) and only a summary of the part count for each Performance.

I have to use the Performance editor before I see parts. Is that what you mean?

Maybe I need to update.

... and if I look at properties in the first Performance of the total librarian - I see what I expect. The Performance name. Its category (which is unassigned and matches the settings on Montage). Comments are blank - this isn't something grabbed by Montage. It's additional information saved into the librarian's proprietary formats and is never stored on Montage.

Because the Performance Editor loads the performance into the Montage edit buffer, not into a slot in a bank.

Because the Performance Editor loads the performance into the Montage edit buffer, not into a slot in a bank.

well that kind of answers my second question: why I cannot overwrite a user performance on the Montage that was called up either with John Melas librarian or with Montage Connect within Cubase. The option to overwrite is not there on the Montage in those cases. One can only store as new performance, which is not what I want because it creates chaos.

So, how can I go around this and edit and update my performances even when I call them up with the librarian or while recording with Cubase? Is there a trick to get it from the edit buffer into the slot or something?

Not on my rig right now, but I think you would have to use the Melas Total Librarian for that.

Or you could do the store via the Montage touchscreen.

EDIT:

The Performance menu has a “Store To” option that might do what you want.