Isboxer 41 and FTL assist/interact

So I havent boxed in about four months and I come back to the new isboxer and am quite confused. My macros/2 steps dont flow like they use to and Im confused on how to implement FTL assist into a macro. So for example, I press R in WOW and that death grip. In isboxer I have the button for death grip set to R also. So i when i hit R it hits R in wow and round robin death grips with my dks. The problem I have though is when i switch targets the slaves wont switch with and tend to stay on target for an additional few seconds and the switch. How do I make it switch targets faster? Also can someone explain the "+ FTL Modifiers from Active Slot" check box inside of keystrokes?

Well I got that working now my main decides he doesnt want to cast attacks while everyone else is working perfectly. Any ideas?