Thank you Ropu for updated 1.30RC1rev1 mod and the included helpful readme and install documentation.

Good to see the payment module install only requires the merging (replacing) of five clearly defined code snippets into four Zen Cart files (/admin/orders.php and three template files). Makes for a straight forward installation.

Some questions/comments regards to a few entries in each doc.

I. README:

A. I'm a little confused by the organization of the section below. Does this info apply ONLY to those whom are running PHP as CGI? Or does the "spoofed messages" issue apply to everyone?
.htaccess Basic Authentication Mode with PHP over CGI?
If your site is installed on a PHP CGI you must disable Basic Authentication over PHP.
To avoid spoofed messages reaching responsehandler.php, set the .htaccess file with the script linked (http://your-site/admin/includes/htaccess.php).
Set permission 777 for http://your-site/googlecheckout/ before running the script. Remember to turn back permissions after creating the files.
B. The following item is listed in the "Common Mistakes" section but I don't see this step listed previously in the readme step-by-step process. Is this set in Google Checkout account on the Google server or in the Zen Cart payment module admin?
Set your Google callback url to https://<url-site-url>/googlecheckout/responsehandler.php
In Sandbox, SSL is not required. In Live mode, SSL is required.
C. The following entry in the readme toubleshooting section references "see above fix" Not sure what that "above fix" is?
Problem: Fatal error: Call to undefined function: getallheaders() error.
Solution: You webhosting company does not have the function getallheaders() enable on your webserver. See above for fix.

II. INSTALLATION

A. Regards to "Option B" for merging code.

I suspect the path below:
2. YOUR_ZENCART_FOLDER/admin/orders.php/includes/templates/YOUR_TEMPLATE/templates/tpl_checkout_payment_default.php
should be:
2. YOUR_ZENCART_FOLDER/includes/templates/YOUR_TEMPLATE/templates/tpl_checkout_payment_default.php

Thanks!
Woody