As the topic says, Import from catalog sets both "filename" and "original filename" fields of each imported photo with its actual file name. Instead it should set the original filename field of the imported photos in destination catalog just like the corresponding field of the source catalog.
My issue: Ihad many small catalogs, in each one I had renamed files with a custom preset "Date-Custom text-Original filename". When I decided to merge them injust one catalog I've lost all original file names (DSC_xxxx.NEF). Indeed after the"import from catalog" process the original filename has become like "Date-Custom text-DSC_xxxx.NEF". I'm importing new files (not from catalog, just the standard import of new photos). So if I should need renaming all the photos with a different structure (and I do), for example "date-original filename"(without any Custom text), I cannot do it anymore with the old ones imported from catalog, as I would have unexpected wrong result. I think it should be very easy toaddress this issue.