Only requires index.php Find in application_top.php
  //Template class require('includes/classes/osc_template.php'); $oscTemplate = new oscTemplate(); Below add:
  // determine the route to load the cm_ modules require('includes/classes/route.php'); in includes/'html_output.php
  //// // The HTML href link wrapper function function tep_href_link($page = '', $parameters = '', $connection = 'NONSSL', $add_session_id = true, $search_engine_safe = true) { global $request_type, $session_started, $SID; $page = tep_output_string($page); Below add:
  $page = str_replace('.php', '', $page); Add to the classes directory the attached file
  <?php /* $Id$ osCompose, Open Source E-Commerce Solutions Copyright (c) 2018 osCompose */ require('includes/application_top.php'); require('includes/template_top.php'); $route = new Route(); $route->load(); $route->listen(); require('includes/template_bottom.php'); require('includes/application_bottom.php'); ?>
What does it do:
It loads the content out of your "content modules directory"

of course that structure is not sufficient.
It is only an idea and trick to get beyond the current architecture of oscommerce.

This will lead into url's like:
Etc etc....   route.php