OK.. I appear to have it working.
The problem with still redirecting to the homepage turned out to be due to me overwriting a line of code in the plugin.
I had to make a couple of changes to make it work as well.
For this url www.domain.com/property/london/thepalace/355 (the final part is the id of the property - the rest SEO)
I have the following config
$settings['property'] = array(
'resourceId' => 10,
'urlParams' => array('location','name','property')
(notice 'property' is the last element)
At line 209 in customrequest.class.php the following debug
echo "<br><br>KEY: ".$setting['urlParams'][$key];
echo "<br> VALUE: ".$value;
in the browser (hence order of urlParams in config above) so I knew the correct data was being created.
I then changed
$_REQUEST[$setting['urlParams'][$key]] = $value;
$_GET[$setting['urlParams'][$key]] = $value;
because REQUEST didn't appear to work.
I didn't realise how easy it is to make Modx create a page for a specific URL with whatever content you want. In my case it might have been easier for me to just take the last part of the URL and send it to the resource as a GET parameter for processing.
[ed. note: xgarb last edited this post 7 years, 6 months ago.]