NoRulesJustFeels

The virtual network interface 192.168.56.1 is confusing the current logic for picking the network interface to communicate with your Chromecast device. Try shutting down that interface.

You didn't set your app Id.

https://developers.google.com/cast/whitelisting#whitelist-receiver

You have to host a copy of the receiver index.html file on your own server and then send that URL to Google for whitelisting the device and get the app...

Provide the debug output by running Fling from the command line: java -jar fling.jar

If you can't get to port 9222 the the device isn't configured correctly. Make sure you have enabled sending the serial number to Google.

Restart your Chromecast device to make sure the serial number is sent to Google.

During my testing with transcoding various video formats, I wasn't consistently getting the necessary duration and current location information during playback.

It is important that the Chromecast device is able to load the receiver HTML file on your network. Its not clear from your description if you have a dedicated web...

Point the Chrome browser to port 9222 of the Chromecast device and use the Chrome debug tools to get more visibility on what is happening on the Chromecast device.