Hi Lawrence,

As you found, Alt-D doesn't do the job; it just brings up the
previous help/more info/table screen. (Joe Mize happened to have
just done a "Go To... Messier" operation; if he'd done something
else more recently, he'd have gotten that screen instead.)

I've added an "undo" function to a test update for Guide:

http://www.projectpluto.com/new.htm

It is currently imperfect (see the above URL for a list of some
items that are not "undoable" yet), but it's not too bad; _most_
actions can now be "un-done".

This update also has some revised code for displaying stars that
may be faster on some systems, especially when printing. If you
should try this update, please let me know of problems in this area
(or any other). The update has not been tested on any machine other
than my own, and I fully expect odd behavior(s) to be discovered.

-- Bill