A thousand thanks, Kino!  I downloaded your macro several months ago, 
but I forgot about it and only today tried it for the first time. 
Previously, I foolishly resorted to converting Nisus files to Open 
Office format to use an Open Office plugin for document comparison.

I used your macro to compare the current version with the previously 
downloaded version of the macro.  Besides minor differences in the 
explanation at the beginning, there are two differences: (1) The 
default setting of variable $frontmostOlder is false in the previous 
version and true in the current version.  (2) The comments in the 
previous version included a link to your website, but the current one 
does not.

(Note to Brian Ferguson:  I believe you can safely keep the current 
version at the URL Kino provided and discard the previous version. 
However, you can use the macro to compare your two versions as I did 
if you have any doubts.)

Thanks again, Kino!
-- 

Bob Stern