Using the bookstore example with pulldata; to simplify, I replaced barcode field with text field, and use shorter numbers (e.g. 688) as id-
When I upload the file Choices.csv, everything works file
When I link via URL, I get the error below (sorry, in German, but the gist is clear). I have checked that https://menne-biomed.de/uni/Codes.csv is downloadable from the browser - it should still work now, feel free to test