Try pinging the Mindstream from command line on your PC. See if it is really communicating. Then try navigating to the device in your browser and see if it has a GUI. You can do this by typing the IP address into the address bar. If you can see the device on your network, and you are able to ping it, then that would mean it is communicating fine. Then comes the web connection. I don't know your expertise in computers, so let me know if you need help with the commands.
Is the web app the only way to access the data? If so, do you need to allow port forwarding in your router to let it communicate to the web?