Looks like the link to the tutorial does not work anymore 
There’s a copy at swiplwebtut/web.adoc at 0602e43b629405c4a67b6085ff65c3b959af7ed9 · rsiddall/swiplwebtut · GitHub
We are working on fixing the menus on the SWI Prolog web site.
my apologies - I turned my server off - we’re integrating them with the swi-prolog site. meanwhile they’re available from github http://github.com/Anniepoo/
There’s also the link in ##prolog IRC greeting message, it still points pathwayslms.