Once installed, then go to your Application folder on your Mac and right-click on the software and press ‘Open’, a pop-up will appear, click ‘open’ again.
I’m sorry about it, and we will launch English Wiki project as soon as possible.
I surmise that you tried to activate MN3 by education coupon code. So you should have gotten an email from us. You may ignore this point “iOS and macOS are separate platforms, therefore MarginNote 3 on iOS is sold separately”.