Activate both options and copy the content from the textarea at the bottom of the page into a file called crossdomain.xml and place it into the root of your webserver, whichs offers the HTTP Binding.
Please note, that the binding is only for localhost, for external access you need to configure a reverse proxy.
Perhaps there is an option for that, but I don’t know it.
It seems, that the domain isn’t correct. I can’t understand.
The webserver, where SparkWeb and the HTTP Binding is running has following DNS name prjtsrv.company.local, but it try to connect to prjtsrv and that DNS isn’t resolvable in the network.