app.yaml apparently not redirecting correctly

I’ve been trying to set up a basic WordPress site with Google App Engine’s new PHP SDK, following these instructions.

From what I understand, app.yaml is where the process kicks off and should work similar to .htaccess (re routing).

Google instruct you to drop your wordpress files into a wordpress folder, so your directory structure looks like this:

.
    ├── app.yaml
    ├── cron.yaml
    ├── php.ini
    └── wordpress
        ├── index.php
        ├── license.txt
        ├── readme.html
        └── (etc)

So their template app.yaml should work, including the following lines:

- url: /wp-cron.php
  script: wordpress/wp-cron.php
  login: admin

- url: /xmlrpc.php
  script: wordpress/xmlrpc.php

- url: /(.+)?/?
  script: wordpress/index.php

But localhost:8080 gives me my app folder’s directory structure, instead of the anticipated wordpress/index.php. I tried this as well:

- url: /.*
  script: wordpress/index.php

Any ideas?

Note: I verified that wordpress/index.php exists, by the way.