Hi Dario,
Thank you very much for the excellent cooperation, I truly appreciate it!
I've tested both of the provided files on my machine, so it seems unlikely that EWX is causing the issue.

As you correctly pointed out, the export process requires temporary environment variables to be set. These variables should only exist within the scope of the Python script execution. Could it be that your system restricts this behavior? If so, the import process might be timing out as a result.
I believe I’ve identified the issue:
In the importer script, the error message triggered by missing environment variables is currently output via a standard print statement, rather than being forwarded to the Embedded Wizard console. This would explain why no error appears on your end, even though the script halts execution due to the missing variables.
I've created a ticket for this, and the issue will be resolved in the next Embedded Wizard release. Thank you for helping us uncover it!
That said, while this explains the missing error message, it doesn’t clarify why the environment variables aren’t being set correctly...
Best regards,
Tim