Server side CORS headers
If you're hosting presentation files from the different domain than the rest of your site then you'll have to configure CORS (Cross-Origin Request Sharing) headers. You need to verify that you have Access-Control-Allow-Origin * header properly set (use debug toolbar in your browser to do it).
If your web server is Apache, then you can set Access-Control-Allow-Origin * using the following .htaccess file (located in the directory that contains presentation files):
<IfModule mod_headers.c> Header set Access-Control-Allow-Origin "*" </IfModule>
Make sure you also configured your server properly for Flash security