Description text in Macros
Windows help files show you how to add a description in custom Macros.
I have tried to follow this but with only one success, and I haven't been
able to reproduce it or edit the description.

There appears to be a step missing. Has anyone tried to add a description to
their macros or functions or edit the descriptions and succeeded?

I know that you can add the description when you are recording the macro,
successfully but I cant subsequently edit it.