Old: archetype-property-<umbracoPropertyAlias>-<fieldsetIndex>-<propertyIndex>
New: archetype-property-<umbracoPropertyAlias>-<archetypePropertyAlias>-<fieldsetIndex>
Basically, this adds the archetypePropertyAlias into the mix, to fix a case where you might have the same Archetype nested on a host Archetype twice (ie box 1 links, box 2 links within the same Archetype - there was no uniqueness)
It also adds in the Property Alias in place of the Property "Index" (unintended side effect, but seems cool :))