I would do this like so:
create a new module and in this module declare:
function YOUR_MODULE_NAME_menu_alter(&$items) {
$items['node/add/your-content-type-name']['page-callback'] = 'drupal_not_found';
}
this will override default page callback for your content type and will return 404 page
Then declare pages you need:
function YOUR_MODULE_NAME_menu() {
$items = array();
$items['adding/your-content-type-name'] = array(
'title' => 'Add new your content type name instance',
'page callback' => 'your_content_type_name_page_callback',
'type' => MENU_NORMAL_ITEM,
'access callback' => TRUE // or whatever you think the access callback should be for this content type
);
$items['editing/%'] = array(
'title' => 'Edit your content type name instance',
'page callback' => 'your_content_type_name_page_callback',
'page arguments' => array(2),
'type' => MENU_NORMAL_ITEM,
'access callback' => TRUE // or whatever you think the access callback should be for this content type
);
}
Declare a callback that will be serving the node edit form:
function your_content_type_name_page_callback($nid = FALSE) {
$node = node_load($nid);
if($node) {
if($node->type == 'your_content_type_name') {
$form = drupal_get_form('your_content_type_name_node_form', $node);
return drupal_render($form);
}
}
return drupal_not_found();
}
I did pretty much similar task in one of my previous projects, so I am sure this approach will work out. May be there are other ways to accomplish what you are after.