The old Kerio 2.1.5 is free, if you can find it anywhere for download. The newer 4.xx Kerio is supposedly in the process of becoming freeware now. You might be interested in this: https://www.wilderssecurity.com/showthread.php?t=286002&highlight=kerio I used it for a while with no issues...
Kerio 2.1.5 still can be had from here http://www.oldversion.com/download_Kerio_Personal_Firewall_2.1.5.html I'm using the Sunbelt's 4.7, the freeware that's in beta. No issues here either.
You might also check the Optimize security in Kerio 2.1.5 thread. I'm not that familiar with Utorrent, but for the most part, the connection alerts will tell you what you need to allow. You will have to make a rule allowing inbound connections to it for the specific port you set it to use. I don't recall if uTorrent required inbound TCP or UDP connections. You'll also need to make sure that your router/modem also allow inbound on that port. Just make sure that the inbound allowing rule is specifically for uTorrent only and not set for "any" application.
