Meter/Tempo markers

So, I was trying to follow the steps in “Techniques for Working with Tempo and Meter” in the Ardour manual.

(I’m using Ardour 4.6.0 on UbuntuStudio 16.04)

But, first thing it says is drag the meter. But nothing I do moves it.

I can add, move, and remove new ones, but the ones there when I expose the Meter ruler, seems are locked.

Same with Tempo.

They are locked at time 0.

Does this imply I should move the track content for the downbeat to be at 0 time?

None of that will work in Ardour 4, which is more than 2 years old.

Current release is Ardour 5.12.

OK, I tend to procrastinate. Is UBStudio 18.x shipping with 5.1.2?
I have 5.1.2 now.