Flash runtime supports loading external content over 80 and 443 ports (non-secured/secured connections).
On Linux OS native ZINC application fails to load content served over 443 port (SSL connection) with public certificate used (issues by CA and available in root certs).

To recreate issue please compile provided flash sample movie.
Click "Load movie over HTTP (80)" to use default HTTP 80 port to load external content.
Click "Load movie over HTTPS (443)" to use SSL connection over 443 port to load movie.
The loading over 443 port fails - while the same content loads successfully within browser or when compiled to standalone Linux projector.

To work around issue load external content over 80 port (non-SSL) or use custom encryption solution based on Flash ActionScript 3.0 raw bytes loading.