Force software to use VPN only with any Firewall application.
Open Comodo Firewall and click Firewall, Advanced, then Network Security Policy. It already opens to Application Rules and where you will control your bittorrent client. If you haven't already run your client since installing Comodo Firewall do so now to be asked to allow and it will be inserted here. Otherwise click Add (top right) then Select (top right, new window) and choose running processes or browse to find (ie. program files/utorrent/utorrent.exe).
You will need the servers IP range that you use to complete the following. It's very simple. While logged in to the VPN and connected to the server of choice (favorite) go here and find the VPN IP address.
Now take that VPN IP and write it down and your range will be the 1st 3 sets of numbers left the same but the last set will be .1 through .255. Example.. NJ US server will give you this 216.155.158.### so the range would be 184.108.40.206 - 220.127.116.11. Simple.
Find the application you want to control in the Application Rules list and and delete it's green allow rule.
Right click the application and choose Add and make the 1st rule "NY IN" (example) leaving source as Any.
Right click the application and choose Add and make the 2nd rule "NY OUT" (example) leaving the destination as Any.
Right click the application and choose Add and make the 3rd rule "Block the rest" leaving both source and destination as Any.
Make sure that the block rule in red is the below the allow rules or it will block every IP including the VPN server. You can move by highlighting and then click move up or down on the right side of the panel. It should look like this..
Obviously this is the 3 main servers I use and you can add as many servers as you like. Just login to the server, get the IP, create the range (ie. .1 -.255) and keep adding but most important is you keep the block rule last.
Click OK (bottom right). Voilà!
Warning! Do not do this to the Safejumper application, OpenVPN, DNS (ie. OpenDNSupdater) and also system and svchost's or you will have problems!