About cs executive exam

sir,

i am doing CA and CS.i need to write my ipcc grp 2 in june.At same dates CS Executive exams also going on.i want to quit my CS exam and atempt it in dec 2014.This june attempt is my first attempt for CS.. can u tell me about how many attempts we can write for CS.and is there any exemption facility same as CA subjects??is there any fee charged by ICSI for Quitting this attempt and for writing in dec attempt??