Did you try to download the app from the dashboard itself, i have not tried this, but lets see if another user can share some information or tips on this matter.
I’ve tried everything… factory restore and any mode of reset listed in the manual have even changed raid types from 5 to 5 wit hot spare then to 10. still have to try JBOD to see if there is a bug some where that makes the App fail to be configured.
I’ve even looked inside these packages WDMyCloud_NAS_Apps_GPL_20150731.tar.gz and xxx_20150720.tar.gz with 7-zip(20150720 failed to install on the EX4 suspect its not a complete package based on the file size)
Neither have a (ATI) Acronis True image.bin file in them so all I can see from this is, its only availible through the firmware update.
The other thing I havent tried is going back on firmware versions to see if that will resolve the ghosted ATI configure button (to do list)