Quote -
You have probably worked out what is happening by now,...

Yes, I had worked it out prior to your post using your code from the thread darkedge mentioned but the extra info is still very useful and much appreciated.

I've just started messing about with the ERC function so have quite a bit to absorb making any examples valuable to me and I am sure to others that are interested in exploring the enhanced rigging options.

Thanks again to everyone that helped me on this problem.