To the several voices who provided input on this subject:

I’ve finally stumbled onto the solution to the problem.

On a fresh copy of antiX-17.5_386-base,  rather than use Package Installer to
actually add a LXDE or XFCE environment,  I used synaptic to initiate, but not
follow through, on an lxde install, and an xfce4 install respectively.
In examining the packages that would be installed in either case,  the only
common packages were libwnck22, libwnck-common, and libxres1.  LXDE
would add libkeybinder0, whereas XFCE would add libkeybinder-3.0-0.  I
installed all 5 packages.  Okular still would not start from the menu, but when 
invoked from the command line while in /usr/bin,  ./okular, it’s file handling 
was improved, but there were still several error messages appearing on the 
terminal.

The error messages seemed to be concerned with dbus access, and varied
somewhat between tests, but the phrase “secure D-bus connection created
before Q Core Application :   Application may misbehave” was usually
there.

On my copy of debian-9.13.0-LXDE (stretch),  I checked the dbus-related
packages installed, and checked if they were also present on antix-17.5.
Package fcitx-module-dbus was missing, so I installed it, but the messages
persisted.

There were web artictles suggesting  that because the okular error messages were 
merely warnings which impeded normal functions, it made sense to simply
modify the okular exec command  in the okular.desktop file to read:

Exec=okular %U %i -caption %c &>/dev/null

with the addition on the end to direct all terminal output to the null device.

With this change in place, okular started from the menu selection and  worked  o.k.
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I want to thank you all for the comments you provided on this subject.   They were very
helpful for deciding what to do, or what not to do, as I careened through the process.

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One might readily construe that the interest displayed herein for okular, to the exclusion of
viable alternatives such as mupdf or qpdfview,  is obsessive.   My fixation is really with the
k3b package, which I’ve found to be the very best CD/DVD burner package, especially with
its read-verification feature.

In a non-KDE environment, any addition of a single KDE-based application invariably
causes the installation of around 100 dependencies, given the extent of the KDE libraries.
But if one is prepared to “bite the bullet” with k3b,  a subsequent install of okular only
adds 7 packages.   Similarly, I often use ktorrent rather than deluge or transmission as
the bit-torrent client.

Thank you all again !!
Len E.