In order to be able to get the link to share with your group you have to first press the “Publish” button in the upper right. After doing this you will see the link to share with users appear as brheal shows above.
I’m adding this graphic to the discussion to help clarify exactly which one to press and which to not press.
Per the discussion above I was still a bit worried about pressing the publish button. I just did it and it works.
