Google have turned down access to the Picasa API, which is how the plugin retrieves photos.
We have released v3.1.5 which will provide access to your images via the Google Photos API as of 15 March 2019.
After 15 March 2019, the plugin can still function using the new shortcodes that access the Google Photos API
They are currently:
* [cws_gpp_albums_gphotos access=own] to list Albums from Google Photos API, use option access=own or access=shared, to specify albums returned
* [cws_gpp_images_in_album_gphotos] to list images in selected album
* [cws_gpp_images_by_albumid_gp id=’6625618881344302193′] to display images withing a specified album, find your id in the plugin Google Photos Album ID Helper page.
You will need to re-authenticate the plugin with Google to use the these new shortcodes.