Yes, I assumed that video would be helpful as well, and I did watch it before posting my question here. But unfortuntately it does not actually cover the specific question that I am asking: namely, what needs to be entered into the "Username" field of the Authenticated Data Source table for Google. You would expect that at around 3:00 minute mark it would have addressed that question, but it does not. Also, it does not cover the "ID Services only" option at all in the video. Neither is it covered in any of the Online Help Center Docs at:
http://howto.caspio.com/authentications-and-connections/setting-up-id-services/
Additionally, there does not appear to be any full documentation for Caspio available for download, nor is there any contextual help feature that documents exactly how to use the "ID Services only" option.
So while I appreciate the response to my post, that does not actually answer my question.
My suspicion is that there is a bug in the current version of Caspio where the "ID Services only" option does not work with Google ID Services only. I could be wrong since I do not have access to any documentation, so I suppose it's possible that it actually needs some special syntax in the "Username" field to be compatible. But if that is not the case, then something is wrong with the current build. So I am wondering if anyone else has been able to make "ID Services only" work with Google.
I can make a Google "Connections" work, so I know that my application is correctly registered with Google, but the Connection's Advanced tab only allows for the creation of a "Blacklist" (which I can also make work, but which is the opposite of what I need). I would like to maintain a list of users who are allowed to connect, not a list of those who are forbidden. However, the interface on the Advanced tab for Connections is different than the interface for the Authentications tab.
When creating a blacklist, it asks for the data source table, and allows you to choose from a variety of fields. When I chose the "IDService.Email" it allowed me to create a working blacklist that rejected Google users based on their email address, BUT the Authentications dialog has no such variety of field choices. It only specifies "Social login field" (whose specific meaning is not explained anywhere). Again, I would assume it would be the Google user ID without periods, but when I enter that (as explained in my first post) it doesn't work.