[web2py] need help testing google checkout with pos plugin

[greaneym]

Hello,

I would like to test the google_checkout_plugin and need some help, please.
This are the names of the plugin I downloaded:

web2py.plugin.google_checkout.w2p and web2py.app.PosOnlineStore.w2p

Does this first plugin provide the functionality (of what is described
in the Google developer documentation) of the XML API, which requires a 
"digital signature" and has
integration with the user's database? 

or does the plugin have functionality of the HTML API, with no 
dig.signature and which requires the user
to login to an account on google checkout and look at what purchases
have been made?

I have a sandbox account and am trying to test but get errors.

With the plugin installed and testing on the pos appliance/plugin,
I am not able to get to the google checkout sandbox.  Do I need some type
of digital signature?

Here is the button info that I think google wants people to use:

Here are the contents of my pos/default/index.html file, where I have 
substituted
numbers necessary.

<--pos index info-snip--->

<img  src="{{=URL('plugin_google_checkout','button', 
vars=dict(next='https://checkout.google.com/buttons/buy.gif?merchant_id=digits_of_mysandbox_acctnumber&w=117&h=48&style=white&variant=text&loc=en_US'))}}"
 
/>

<form method="POST"
      
action="https://sandbox.google.com/checkout/api/checkout/v2/checkout/Merchant/mysandboxacctnumber";>

  <input type="hidden" name="cart" value="stringnameofmycart">
  <input type="hidden" name="signature" value="REPLACE_WITH_SIGNATURE">

  <!-- Button code -->
  <input type="image" name="Google Checkout"
       alt="Fast checkout through Google"
      
 
src="http://sandbox.google.com/checkout/buttons/checkout.gif?merchant_id=mysandboxdigitsacctnumber&w=180&h=46&style=white&variant=text&loc=en_US";
       height="46"
       width="180">
</form>

I do not see the image of the button, but I see the text "google fast 
checkout" and when I click on that I got a 503 error.
I've made sure that any long lines are continuous and not interrupted by 
spaces or carriage returns.

I appreciate any help. 

Thank you,
Margaret

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