Can't add a library from another provider in Plex Cloud

Hi,

I've been trying Plex Cloud through DropBox for a couple of days now, but the uploads are HORRIBLY slow (30 minutes for a 2.30 Gb movie). So I tried Google Drive just to compare speeds, and it's MUCH better (3 minutes for the same movie). So I tried to add my Google Drive to Plex Cloud, followed all the steps, went to Plex Sync on my account, added Google Drive... NO SUCCESS. When I want to add a new movie library, Plex only lets me choose a file from Dropbox. I can't go onto my desktop, or choose a file from anywhere but my Dropbox. I even deleted my dropbox library, and unsynced it from Plex Sync, but nothing changes.

Thanks for your answers!