On my system Killswitch consumes a lot of CPU even if I do nothing.
From time to time it jumps from 20% to 70-99% of the CPU.
http://i.imgur.com/W7WaX.png
Have you got the same?
Windows 7 Ultimate x32
Comodo Internet Security installed
AMD Athlon 64 X2 Dual Core Processor 3800+ 2.01 GHz