Is there only one trail version permitted?
Lightburn allows 3 seats per license. Should not be the problem.
Let’s cover the basic troubleshooting first….
Does IMPORT the .pdf work on your Macbook?
Does any other part of the program work on the Macbook and not the mini?
Always help us by showing us what you are working on. Where is the .pdf? Post it here so the hive-mind can actually put the issue to test on known and proven systems. Use this icon to upload. Append the “.pdf” to “.pdf.png” to allow the upload.

Try changing the extension from .pdf to .ai and see if that will open.
Changing the extension from pdf to ai did work. On the MacBook the pdf just imports thoigh
uploading won’t work
Then change the .pdf extension to just .txt. the forum has some upload restrictions for security. The on the download side, the .txt is changed back to .pdf.
Looks like your issue was resolved.
Good luck
Thank you for the quick replies