Thanks!
I just tried again, going there directly, and got the following:
Aug 11 21:28:57 montypython httpd: PHP Warning: main(Date/Calc.php): failed to open stream: No such file or directory in /home/httpd/html/horde/kronolith/lib/base.php on line 55
Aug 11 21:28:57 montypython httpd: PHP Fatal error: main(): Failed opening required 'Date/Calc.php' (include_path='.:/usr/share/pear') in /home/httpd/html/horde/kronolith/lib/base.php on line 55
Which is sure saying that something is wrong, but, since I am totally unfamiliar with the app, I sure don't know where to look!
(I used the versions of horde, php, and kronolith that were called out in the How-To. I noticed that there is a newly released version of kronolith available on the horde website, but it's not in rpm format and I'm not sure how to install it, or even if I should install it).