WD My Cloud hangs with external USB storage

[SQ5]

Looks like that has been attempted, unsuccessfully so far, within this thread:

http://wdstagingsplit.staged-by-discourse.com/t/guide-building-packages-for-the-new-firmware-someone-tried-it

Maybe some progress towards the right kernel in this thread:

http://wdstagingsplit.staged-by-discourse.com/t/mainline-kernel-4-11-x-for-wd-my-cloud-gen2