Need overview on WSPEventSelect API

At the moment I am relying on _DataArrival, _SendProgress and _SendComplete to change the colors of two shape controls (red box is idle, green box is rcving/snding) but it isn't accurate (rcv depends on how long _DataArrival is executed not reception of data) and plain ugly to watch (flickers a lot, since I am still calling the update proc even though its currently green). :)

I was wondering if there's an API to know when a frame is being sent/received or idle so I can update the colors of the shape controls (or is there a better way than the shape controls)accordingly.

So how does the LAN connect status icon in the system tray know when to blink? Anyone? Even just the name of the function?

Can anyone here give an overview on the use and possible application of WSPEventSelect API in somewhat layman terms?