Due to the limitations of Google Drive API, downloading files from Google Drive now requires configuration.
Please read the following article for details on how to configure the settings.

You need to install the file-sharing app to import any file from the service into the app.

1. Please go ahead and install the file-sharing app.
   • Google Drive app
   • Dropbox app
   • Box app
   • One Drive app
     
     
2. Launch Piascore app
   
   
3. Go to Download > Cloud
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4. If "Files" doesn't appear on the list, please add "Files" from "Add Storage."
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5. Tap "Files"
   
   
6. You can find the files sharing service's icon on the left of the screen and tap it.
   • 
   • If you can't find it, please see the following.
     • Use third-party cloud apps in the Files app - Apple Support
       
       
7. You can download files!🚀

If you would like more information, you can read this article.

Use third-party cloud apps in the Files app - Apple Support

Cloud file-sharing service