The readme file only mentions that there should be a zip archive containing the web apps but it doesn't specify more. I went ahead and downloaded the archive from https://github.com/SAP-samples/cf-mta-examples/tree/master/content-deployment/content to investigate its internal structure.

I saw that it uses the following structure:

content.zip
|── webapp1.zip
|── webapp2.zip
|── webapp3.zip
| |── manifest.json
| |── xs-app.json
| |── ...

My ask would be to add this information to the readme to make it easier to find.