Hello,
None of the image references in your CSV tables include the filename’s extension (.PNG) so whatever method you use to host your images, as long as there’s a mismatch between the filenames (ie. lacking the extension, in your case) the references simply will point to an invalid URL and no image will be found
Re. the zip file in the S3 bucket, it’s not public: when I click the link in your message, I get to the sign-in AWS portal. If I cannot access the zip file manually, a fortiori I cannot access it in the background when taking the experiment either
Jeremy