I’m low on time or news today, so here’s a Xenia update:
The pink xenia (sold to us under the name of Pom-Pom xenia) recently decided to go questing for the light. It leaned against the rock above it, attached, and then started stretching upward. You can see it and its original footprint here:
I’m guessing that it has a month or so until the foot detaches and moves up to join the new base.
Our original xenia is still spreading, and still acting contained and tiny. 
We had two failing offspring that we moved to the refugium, in the theory that the lower light would make them happier. One of them disappeared two weeks ago — very odd, it wasn’t miniscule — but the other is a complete free-spirited pulsing creature, and it’s already split off to make a twin. It really looks like the light is the difference, since all other parameters should be comparable.