Thanks a lot for your feedback.
Yes! I can encapsulate a zip file in a rtf file. I can import the rtf and I can see the imported rtf file in the folder. The rtf file appears in the requirement as an icon with zeros & ones. Therefore, importing a data file in a requirement should be perfect.
But then, how to download / extract / identify a document that is encapsulated in a requirement, except opening the xml in a text editor?
Thanks in advance / Best regards.