How to do p2p port forwarding.

Please help me out to do port forwarding in mikrotik.i searched alot.my peer2peer download is working but port forwarding makes performance high.if anybody knows that then put a post here or send me a mail at kingofkingsofpirates@gmail.com

http://forum.mikrotik.com/t/untorrent-help/19613/6

I have done DST NAT rule but it is not forwarding port.let me make it clear.actually what we have to day.make a clear explanation.