Reply To: Please help – we're stumped!

Researching Google Drive Filestream, I came across this, perhaps it is the key to your problem?

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Making Files Available Offline
By default, Google Drive File Stream does not store a copy of your files on your local computer. This means that if you do not have an Internet connection, you will not be able to access these files. In order make your files accessible offline, right-click on a file or folder and select Available Offline under the Drive File Stream menu. Please note that doing so will store a copy on your computer, using up more of your hard drive space.
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I don’t know how your workflow is set up, but I would strongly recommend that all folders containing InDesign files and their linked InCopy stories be set to “Available Offline” for all users who need to open/edit them. As I said the linking and file locking/unlocking involved in the workflow is rapid and somewhat fragile even when files are physically stored on your own hard drive (as with Back up and Sync, or Dropbox, etc.) and if you’re relying on the service to sync these in the cloud on the fly, that’s asking a bit much, in my opinion. They’re mainly designed for single-file usage like MS Offfice files, not for files with many shared, dependent links like InDesign/InCopy docs.

AM