An example of one of the cases, which you can see is already known but still displaying as not known?

You probably need to cache your recipes. In order to do this you need to open up your profession windows so that the data can be pulled. Blizzard won't send addons this information unless you have opened up the profession window once with the addon.

There is currently a bug where you need the "Show the Profession Mini List Automatically" turned on and then open up your professions.

Once you open it up, your chat log should say "Cached X recipes" then you will be able to look at recipes and that error shouldn't occur.

Odd, thought I had, thanks for the quick fix and I'm an idiot! :D