My understanding is that you might need to adjust the Window Rectangle coordinates, until they overlap your Grid Frame properly.

Also that you only need to pass the click to the Priest, so probably not to all of w1, w2, w3, w4 and w5.

There are several separate elements for Repeater Region healing.
One is the Grid Frame, with an alphabetical sort... sounds like you have that.
Another is passing the clicks to the desired toon.
Another is setting Clique to interpret which heal to cast based on the click received; configure that in warcraft, and on your Priest.