Download the plugin here: https://github.com/oklink/oklink-wpecommerce/archive/master.zip

PHP >= 5.3.0 with curl, openssl

First generate an API key wat https://oklink.com. If you don't have a Oklink account, sign up at https://oklink.com.

Download the plugin and copy the 'oklink' folder and 'oklink.merchant.php' into wp-content/plugins/wp-e-commerce/wpsc-merchants on your server.

After copying the files, open the Wordpress dashboard and navigate to Settings > Store and click the "Payments" tab. Next, check the box beside "Oklink", enter your API credentials, and click update.