On the page https://koha-community.org/calendar/ is a link 'g+ Add to Google'. I tried it out and google calendar reports an error message: "This email address isn't associated with an active Google Calendar account: https://koha-community.org/?plugin=all-in-one-event-calendar&controller=ai1ec_exporter_controller&action=export_events&cb=1986744256. Please check the email address and try again."
The content of attachment 56713 has been deleted for the following reason: spam