One of the great features of the Google system (gmail, calendars) is it’s ability to integrate with the Google Drive - sharing folders on the drive with users and calendar… there is an attachment feature in the eM Client event definition but it doesn’t seem to do anything other than allow you access to a list of files associated with the event. It would be very cool if eM Client could integrate with Google Drive - upload attachments to G-Drive.
We decided to not implement this. When you install the Google drive on your computer, you will be able to use it in eM Client as any other folder.