Here's what I did to add in the Val'anyr proc.   Not sure how accurate it is, but at least it makes it best in slot!

Right click it to edit:

You'll see this screen, click Add button, under Special Effects.

Bringing you here.    Enter those numbers for the CDs, durations, change the Trigger to healing spell hit.    And from the above menu for the effect, scroll down to Equipment Effects, and enter 0.15 for the % Shield from Healing. 

And you're done!