Nicolas, it technically did not resolve the issue in full...
I downloaded a fresh copy of HikaShop 2.5.0 which was the most recent release available to me...and oddly enough, it was the same numbered as what I already have.
I unzipped it first, then uploaded via FTP, and installed from directory. Per Joomla, it installed correctly, so I waited a minute, went in to my cpanel, and flushed the cache just to be safe...and yet it still during searching, gives me the 404 error code when clicking on the results of a search...BUT, it is allowing me to click on a link & give me a few returned searched items as full page. So it's partially working.
If you go to my site, click shopping, then in the search box type Osteon...it will give you 4 results. The results for the Osteon Prime and Osteon Jaguar give me a 404...whereas the Osteon D and the Battletech Blog links go all the way through to the proper page.
If you search for Rotunda, it will give you 1 result, which leads to a 404 page as well.
Another example,
Any other thoughts?