How to make work with nginx (perusio's config) changes to drupal.conf

First of all, this module is incredible. By far my favorite that I use. Thank you contributors.

My Stack:
Drupal 7.31
Nginx 1.6 web server (Perusio config)
Note: I have disabled memcache and varnish, stopped services, and commented out anything related in settings.php to simplify the problem for troubleshooting

Authcache Specifics:
(in settings.php)
/**
* Setup front controller for bootstrapping
*/
$conf['authcache_p13n_frontcontroller_path'] = 'authcache.php';
/**
* Required configuration for Authcache Builtin Storage Backend.
*/
$conf['cache_backends'][] = 'sites/all/modules/authcache/authcache.cache.inc';
$conf['cache_backends'][] = 'sites/all/modules/authcache/modules/authcache_builtin/authcache_builtin.cache.inc';

(in drupal root)
copy sites/all/modules/authcache/modules/authcache_p13n/safe_frontcontroller/authcache.php

Problems:
404 (Not Found)
https://www.example.com/authcache.php?a=search_box&r=frag/form-token&o[q...
https://www.example.com/authcache.php?a=&r=frag/menu-local-tabs&o[q]=nod...
https://www.example.com/authcache.php?a[nh][u][0]=61&r=setting/node-hist...
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Possible Solution:
I believe the issue is related to this GitHub case on Perusio's config; however, I have tried this over and over a variety of times and can't get things to work. I have tested on Apache with local setup and things work great. But once Nginx comes into the picture, I have problems.