Yes, I wasn't getting what you were saying because you kept saying 8920 was working inside but 8741 wasn't working outside. On DSM 7 internally Emby will always listen on ports 8096 and 8920 and you can't change this from the UI. It should make no difference what the SSL port is internally as you don't need to use it inside your network as you don't need things encrypted so port 8096 is fine for local use. For remote use you can change the external/wan port to be anything your want for