JHT on "My last update was 2013 Now get error 404 trying to navigate"

Have not accessed my site for several months. I now cannot navigate beyond my homepage http://www.trageser.us/gallery
When I click on any image I get the error 404 message.

Currently installed version is zenphoto-1.4.1.6. Noticed latest version is 1.4.12.
What is the easiest way to fix the problem.

I am retired now and would rather not learn a new language.

Jim Trageser
(jim@trageser.org)