I haven't been able to figure out how what you are asking either. But as a work around we put a hyperlink in the header of the page with any special instructions.
The file you need to edit (back it up first) is codebase\netmarkets\jsp\changeRequest\create.jsp
after the following code
<cwiz:initializeChangeWizard changeMode="CREATE" varianceEffectivity="false" annotationUIContext="change" changeItemClass="wt.change2.ChangeRequestIfc" />
I put in a <div> with the info I wanted
<div class="x-panel-header attributePanel-label" style="text-align:center;">Special Instructions: <a href="YOUR URL" target="_blank"><img src="/Windchill/netmarkets/images/info.png" > Click here for SOME MESSAGE</a></div>