[dmdsoftware]

I assume you created the link Google Photos in. Everything should be accessible. Which version are you using of the plugin? gdrive or gdrive-testing? Photos are omitted if viewing from Video, by default, unless you change the plugin settings to filter nothing, or view in Pictures plugin.

Ah, that was it! I had not checked the option from Google Photos to "Automatically put your Google Photos into a folder in My Drive" ... after I enabled that option in Google Photos settings, everything showed up and works perfectly Thank you!

This definitely does the job in terms of easily accessing photos and videos from Google Photos using Kodi. Have you thought about developing a stand-alone Google Photos add-on? Google is deprecating PicasaWeb and that add-on doesn't work for new users, so the author is suggesting somebody develop a separate app for Google Photos. The ability to access photos, videos, and albums (local or shared) would be pretty awesome.

You answered your own question Google stopped really being open some time ago, and when they release new products, they don't tend to release APIs for them. They released an API for Picasa, and as you noted, it is depreciated and only some time before it disappears. Google never released an open API. There is an API behind the scenes, that the web site and phone apps use, but it is closed. Google doesn't obviously want people developing apps that utilize Google Photos. We are fortunate of the tie-in to Google Drive so that we can use the Google Drive APIs.

How do shared albums work? Do they also appear in your Google Drive, or only your own albums?