Localhost socket error 10061: connection refused

I am unable to connect NetGenius. The exact error is localhost: Not connected (socket error # 10061: connection refused.)

A side question: can I monitor requests made via specific apps, like get/post details etc as I would in a browser?

That error means the NetGenius window can't reach its background service. Please do the following:

• In services.msc, check that NetGenius Core Service and NetGenius Traffic Processing are both running. If one won't start, Event Viewer → Windows Logs → System usually says why.
• Make sure that your antivirus hasn't quarantined NGDriver.sys or blocked NetGenius on port 8702.
• If the services aren't listed at all, rerun the installer with NetGenius System Service ticked.

On your other question, no. Almost all app traffic is HTTPS, which is encrypted, so NetGenius can show which app connects where and how much, but not the GET/POST details. For that you need an intercepting proxy such as HTTP Toolkit. It works with many apps, though not all, since some ignore the proxy or refuse interception by design.