Google Checkout - Discounts

Hi NopC Forum.... Using v1.8 & Vs2010pro

Created a Discount £5 off first purchase...

Admin/Promotions/Discounts.... Added New Discount...
Assigned to Order total
None
Unlimited
Name:  Intro Offer
Unclicked
5 (GBP) currency
10/20/2010
10/22/2011
Clicked
5offer

Works great - see it in the cart after you add the Discount Code... "5offer"

see the product at £15 with Discount of -£5 etc.... so new total is £10

When you check out with Google Checkout...  in sandbox mode - Total is £15.00 (plus in the emails to test account for £15.00)

(When purchased in Google Sandbox - the order in NopCommerce CMS Sales/Orders = £10.00 - which is correct)

Conclusion - the client is still charged £15.00, and discount is not passed to Google Checkout -

Anyone help with which coding to change or any example code would be great?
cheers Simon

There's a notice on Google payment method configuration page:

> Tax is not supported.
> Discounts are not supported.
> Checkout attributes are not supported.
> Reward points are not supported.
> Gift cards are not supported.
> Shipping rate computation method should NOT be set to real time methods like USP, USPS.