Specifically, one of the ouput properies was not being set.
Unit tests checks of the output properties have been added.
The failure of the example was due to a change made by Pete in a previous ticket, but I've update the help text.

It was always logging (to debug) that it wasn't doing anything. No
it is a bit louder about it.

...in the peaks table of slice viewer.

I love working towards encapsulation.

This a step towards having the visible columns settable.

It checks for RectagularDetectors, technique, and the facility.