Problem opening Sciv. 2 files in Scriv. 3

Scrivener Scrivener for macOS
1

I’m downloaded the latest 3.1.4 version of Scriv. 3 onto my new iMac running Catallina 10.15.1. I’ve been using an old iMac and Scriv. 2. I saved these old Scriv. 2 files to iCloud drive as backup zips. On my new Mac, I download such a file and unzipped it but Scriv. 3 says the document cannot be opened. How can I open it?

2

With the help of Apple Community support I was able to solve the problem which lies with Apple’s Permissions. Here is the link for others who might have the same problem:
support.apple.com/en-us/HT203538