not sure that Comodo Firewall works proper (Win7 64)?

I have PC with XP and laptop with Win7 (x64).
On XP when I open Comodo firewall I can see in the traffic section different programms connecting with Internet - most % for system, then email programm, Firefox… but when using Skype also Skype is there. I can also see green or red arrows in the Comodo system tray.

No I noticed that on the Windows7 (x64) in the traffic section there is only and always System 100%, doesnt matter if I download big file or talking in Skype. Also there are no green or red arrows in the systemtray icon…
Is this normal?
PC with XP is connected to Internet via LAN, laptop with Win7 via WLAN but I dont think that this affects something.
The issue sounds like this one here

I am behind a router with firewall function