New help text

[Tom Humphrey]

I've added extra help text to the documentation form, which I hope will be useful, particularly for new users. However by making the form longer it may also cause problems. If the new extended help text makes things more difficult for you e.g. by making the form window scroll too much, then please follow up this post with your comments.

Please note that you can turn of the additional help messages by clicking a link at the bottom of the form.