If you receive this message during import of demo content:
Oops, Unyson Backup requires PHP Zip module but it is not enabled on your server. If you are not familiar with PHP Zip module, please contact your hosting provider.
just make sure to enable zip extension on your server. Some providers disable this module by default, but very often there is an option on cPanel which allows you to enable it with one simple click. However, if there is no such feature, you will need to contact your hosting provider as suggested in alert message and ask to enable zip extension on your server. More details can be found here