I am trying to import jpegs into LR Classic. These are scans of old negatives. They are on a new external SSD. I am leaving them in original location, so just adding to catalog. I have latest version LR Classic and Macbook Air M1 with BigSur 11.2. LR not rendering minimal previews, or just 2 or 3 out of the batch. Import is very slow and fails midway. Error message 'Some operations were not performed'. 'An unknown error occurred'. Importing raws from SD cards working fine and I have no other issues. I'm new to a Mac so unsure where the problem lies or what it is. Any help gratefully received.