I just found a better way to do this. Sorry for reviving the topic, but I think this is an important feature for bigger websites.
You need to add the next definition to your routing
array(
'pattern' => 'folder/(:any)',
'action' => function($page) {
$site = kirby()->site();
$page = page('folder')->children()->find($page);
tpl::load(kirby()->roots()->templates() . DS . "folder/$page.php", array('site' => $site,'page' => $page), false);
},
'method' => 'GET|POST',
)
this will work, and you cas use different blueprints for every oage as it loads the right page into the $page variable.