We need your non custom domain so that the PowerUps can be installed. You will be asked for this every time you go to install a PowerUp.
How to get your domain:
Be sure you are logged into yuour site as a Site Admin (or Partner)
Go to Settings / Site Url
Copy the text that is in front of
.thinkific.com
in the My Thinkific Url settingDo not use the "My Custom Urls"