Application's inner links vs firewall?

At the last week me, my gf, some of my friends - who had comodo firewalls - noticed the following:
Version 1: after a while, the Internet connection got a freeze, svchost.exe generates an almost 100% CPU usage. I only noticed this version of problem at my GF. Don’t know what the problem could be but - it seems - caused by comodo (cmdagent and the service shared almost 50-50% before i shut down the other exe). She got an up to date avg av, connecting to the Internet by a router (so do i).
Version 2: after a while (takes hours), the Internet connection goes away (browser hangs). These were on systems got IE7 eng (just an info, i don’t know if this is important or no).
At version 2, it seems comodo got problems when i activate links through applications, fe. features like inner links (search update button, buy program lin, etc.). I had a problem with Microsoft Outlook 2003 (after clicking simple links) and WinZip 11, too. I didn’t deny them.

Got any ideas how to track down the problems?

EDIT: just an updated text.