The current version of Circle² is 2.2.1 and here's how to get it.
FAW Account
If you have a FAW Account then please login to download the update.
When you click on the Downloads tab, you'll see something like this:
Click the yellow button for macOS or Windows to download the installer and follow the usual installation steps.
FAW Downloads Page
If you do not have a FAW Account, or you do not have installers inside your account, you can access the latest installers here.