On the LV Server, in order for CORS to work, update the property liveview.server.allowedOrigins=<hostname> to specify the hostname of the WebPlayer Server. Add liveview.server.allowedOrigins under systemProperties in engine.conf:

LDMEngine = {
        systemProperties = {
              "liveview.server.allowedOrigins" = "hostname"           
        }
}

The correct hostname format for an origin is:

scheme://hostname:port

for example:

http://myapp.example.com:12345
https://myapp.example.com