OScommerce Coupon Module + fix Google Coupon

Hi, We are looking for an expert to install Modules for Coupons and Gift Vouchers and fix Google checkout Coupon error as soon as possible. 1. For the Coupon Module, you can use this Contribution or the one you find more advanced and/or reliable: [login to view URL],4213/category,all/search,coupon 2. For the Gift Vouchers Module, you can use this Contribution or the one you find more advanced and/or reliable: [login to view URL],282/category,all/search,gift 3. We also have a minor problem with Google Checkout Coupon. We have somebody from GetaFreelancer installed Google checkout level 2 to our site. However, when we try to generate coupons, they do not work. (When they checkout via Google Checkout, the box for entering Coupon Code shows up. However, after entering the code, there's a message saying: Your Coupon Code can not be used this time. We check the Integration Center in our Google Checkout Account, and find the following error: -------------------------- We encountered an error trying to access your server at [login to view URL] -- the error we got is: [login to view URL]: PKIX path validation failed: [login to view URL]: basic constraints check failed: pathLenConstraint violated - this cert must be the last cert in the certification path -------------------------- Also, we don't know what to fill in for API Callback URL, and what Callback method to choose (XML or name/values pair) We expect that an expert should take less than 1 hour to fix these minor issues. Experts who can communicate via Chat are preferred. Our website is: [login to view URL] . Good luck in bidding and Merry Christmas! Regards, Nguyen Nguyen