Such "unawareness" of Windows updates may be happening because NetWorx runs as a regular application, not as a service. This means it can miss traffic that occurs before a user logs in, for example, automatic updates downloaded by the operating system itself.
Will NetWorx ever run as a service? This post in 2011 says it may be possible in the future. Has there been any progress on this? Other bandwidth monitoring software such as DU Meter are able to run as a service.
We did have plans to implement NetWorx as a service, but eventually decided not to do it. Doing so would essentially mean a complete rewrite of the product since it's too tied to being a regular app.
Instead, we are currently working on a new product named NetMaster, which will run as a service. It will also have several advantages over NetWorx, including live usage display, speed limits for applications, and traffic prioritisation. It should be released in November.