Nocat overwrites my iptables script

Hello.

Hope someone is out there.

I installed NoCat in Open mode and everything works fine. The
installation was made on a box that was already running an iptables
script blocking some ports and P2P programs. After installing NoCat I've
noticed that all clients were connecting to the "blocked" ports and
using the P2P programs. I came to a conclusion after checking the
packet's traffic (iptables -L -nv) and noticing that evertyhing on my
script was ignored and the rule from NoCat was the one being used (
NoCat_All in the PRETOUTING table ). How can I change this? I would like
NoCat to capture and permit as it intends to do but, I also would like
to have my original script running along with NoCat.

Thanks in advanced for your help.