I recently saved my scrivener files on google drive for the first time and when I downloaded them to work on I discovered all the body text in the files was missing. When I look into the saved document in Gdrive the text seems to be there, but appears to vanish between download and opening. Am I doing something wrong, or is it a bug?
You might just be better off resuscitating from your backup of those projects. You did backup your work before hazarding your files to a cloud service, yes?
You should have some backups created automatically on closing your project. If you have some from before moving to gdrive, you could copy that out of the backups folder and use it as your project.
You can get to these automatic backups by looking at Scrivener->Preferences->Backup, which has a button that will open Finder to the backups folder for you.
The fundamental problem is that a Scrivener project is actually a folder, with subfolders and potentially hundreds of component files. The issue is most likely that Google Drive isn’t treating it as one: you’re getting just the .scrivx file, which is the master index used to build the Binder.
One potential solution would be to force Google Drive to compress the entire .scriv folder into a ZIP file, download that as one unit, and then unzip it locally.
Another option would be to install the Google Drive software on the local computer, allow it to sync to the server, and then move the (hopefully complete) project out of the Google Drive folder using Finder.
If neither of those options helps then yes, recovering from a backup is probably the best alternative.