I used the 16.3 Pro he previously uploaded. I didn't have to activate or anything. Anyways, I'm downloading now. will give you feedback once I finish installing.
EDIT: no activation needed.
I already have Zorin 17.1 Core . already installed needed apps. I tried the Pro, it's basically the same with additional apps. most of which I don't need and can easily install if needed. what I only did now is copied all the python scripts for the Premium Zorin Lay-outs from the Pro installer. hence, my Core version now has all Premium Layouts.
Again, thanks for posting!