Cool ideas, thanks for your contributions! You mention that there's an interface AutoIt <-> Rainmeter. Here's also a solution for Autohotkey <-> Rainmeter: Commanding Rainmeter with AHK (and vice versa) and one more concrete skin <-> AHK example.
The TCPView Autohotkey script (tracking the complete TCPv4 and v6 connections including resolving hostnames) showed no visible CPU load on my machine. Generally, AHK is extremely resource-efficient - all my AHK scripts (I have quite a few running including loops with various background checks independent from regular hotkey-scripts) are never visible in my Top5 CPU process monitor (=Gadgets CPU meter ) while Rainmeter.exe is always visible there with a constant 1-2% CPU load (running Gadgets CPU, Drives + Network skin and a modified RSS reader, weather and a custom-made medical tracking skin). So using Autohotkey for pulling the Top5 network connections incl. resolving hostnames should be very resource-friendly. I'm a hobbyist with just 1 year AHK v2 experience, willing to contribute. However, for hooking into those MS functions: new to me, would need to deep-dive and "learn by doing". The AHK forum community is usually very helpful and agile to find solutions to any scripting problems, so this could be an approach. Anybody else here supporting this or would you rather go for AutoIt or something else? I know AutoIt it's similar to AHK but I have no experience at all.
Regarding Windows 7 support - well, those machines hopefully anyway are not connected to the internet any more, so why should they need a network connection monitor? Honestly... Ok, there might be very specific applications in an isolated private network but this should not stop us from developing such a meter. It's just another optional feature, so the skins still run on Win 7 machines.
@SilverAzide: "Not possiböe" was your first reaction and follow-up feedback war also focused on disadvantages and risks. You're not convinced yet, right? What do you say, how can we make this happen? I'd say "never give up - everything's possible"