FTL is built in to ISBoxer. Here's a few threads but I think you'll need to post your config and wait for someone who can read it if those don't have the answers or you can't find any troubleshooting threads.

https://www.youtube.com/watch?v=G5q17b7W74c
http://isboxer.com/wiki/WoW:FTL
http://isboxer.com/forum/viewtopic.php?f=4&t=3653
http://isboxer.com/forum/viewtopic.php?f=18&t=394
http://www.dual-boxing.com/threads/4...use-FTL-Assist