Tried to create a periodic snapshot task, and could no create it. After clicking save, the WebGUI rejects the dataset chosen saying "Select a valid choice. tank/Backups/Dropbox is not one of the available choices." This is a bit whimsical since it is a dropdown.
I can reproduce this trivially. If a dev would like to see and debug this on my personal FreeNAS, have them contact me via Ryver.