Do you mean the associated fields don't show as already selected on the update page?
I thought that code was added automatically, but if you attach a copy of the page in question I can take a look and give advice.
Your friends over here at WebAssist! These Dreamweaver extensions will assist you in building unlimited, custom websites.
These out-of-the-box solutions provide you proven, tested applications that can be up and running now. Build a store, a gallery, or a web-based email solution.