If its a simple chain you can add the erc control manually in wordpad. Its a bit tedious but doable.

There is a pdf document on erc controls available at http://www.rbtwhiz.com/rbtwhiz_ERC.html,
or  http://www.atlantis23.com/erc_download.html

The easypose utility is certainly worthwhile if you are going to do very much.

Chains mess up because there are too many degrees of freedom in the joints.  So unless you pose each joint individually Poser messes up . In Daz studio simply select the range of all chain parts , and move the selector to bend the chain. The multiple select in Daz studio removes the need for simple erc code .