hi Beobee,
The reason you will still see ping activity from them while using the 1.9 patch is its way of disconnecting them. Unlike other programs that deny any connections at all instantly, the patch is designed to delay the disconnection.
This will allow them to communicate with your machine in that brief time.
The communication is alot like begging for a connection agreement. Because the design of the patch is a 'Just keep em talking, and busy' sort of approach. Makes them use more resources, and wastes more of their time tring to make the connections.
Remember that if your seeing them on a firewall or peerguardian this is a sign the communications are being blocked from those respective programs. The nature of the dll patch will allow your firewall or Peerguardian to see the activity of them 'Begging for a connection from your machine' and block it there also.
The answer to your questions is no, you dont need to run peerguardian with your Patch in order to block them from the network. The amount of communications they are able to get in durning the few seconds they 'Think' a connection agreement can be reached shouldnt be enough to allow them to make your connection unstable. The dll doesnt allow them to make an actual connection, just makes them think that maybe there will be.
Hope I havent confused you more, as I mentioned the answer in the simple form is just No its not needed. If you however, feel more comfortable using the Peer along with the Patch feel free they work together just fine.