Hi Barry:

In response to:
""I think a node for notes would be a good idea to give some reference rather than adding a separate text file.""

One good thing about using nodes>extensions>Documentation is that multiple languages are supported.
So far only EN and FR, as far as I know.
Although only very few nodes have any such Documentation at present. I did 2 or 3, just to learn how to do it, quite a while ago.

I do not know how to do the messaging that you have suggested.
The messages would have to be stored somewhere.
So maybe have the message node access the Doc somehow?

- Brian