PL5 Searching doesn't work properly for all keywords in an hierarchy - only for "Selected" keywords

[platypus (Canon & Mac)]

@Musashi

1/ Preference to apply all KW hierarchy to an image or just the selected child
We will add a preference to apply all KW hierarchy or just the selected one, this preference will be added in the Preferences menu.

2/ Compatibility mode
We will add a preference to add the keywords hierarchy in “DC subject”

These two points are unclear or even redundant. Can you give us examples of how XMP would look in the four possible cases?

How will DPL deal with the new tag that was recently introduced in Lightroom: <lr:weightedFlatSubject>? As of now, the tag seems to be taken over to XMP written by DPL 5.1.3 and other versions.