Just to mention that I got an email from Dropbox saying that on 1st September 2017 they are discontinuing the use of the Public folder mechanism which I've been using to host the Pretty Deep Maps mentioned in my sig (I guess they consider hosting websites via Dropbox to be some kind of unforeseen usage and hence are killing off the possibility?). Since the distribution is very large it may be some time before I find an alternative host so if anyone wants the charts it is best to download in the next 7 days! I do have a new version planned but since it involves a major rewrite in Python it is still some months away.
Martin