Turns out that amazon requires a crossdomain.xml file for x-domain messaging in flash. Here are the steps to solve:
1. First create a file called crossdomain.xml with the following content (The file name must be exact.)
<?xml version="1.0"?><!DOCTYPE cross-domain-policy SYSTEM "http://www.macromedia.com/xml/dtds/cross-domain-policy.dtd">
<cross-domain-policy> <allow-access-from domain="*" /> <allow-http-request-headers-from domain="*" headers="Authorization"/> <site-control permitted-cross-domain-policies="master-only" /></cross-domain-policy>
2. Replace the two *'s with the domain you are going to access content from.