Hey Thanks Zem for your reply,
but i have identified where and why its giving glitch and found a workaround also for it.
1) the issue is not with "copy" node, if i use it just below the multilayer(hardlight) node it gives glitch. in all the other places its working fine.
i started using just above the multilayer node and using it right now, still to findout why its causing the issue,
and Shake V4.1 yes this eve we are upgrading to it. we already have license.
thanks
Nishok A