Hi Jun,
I figured out that if I save the list as a template in SharePoint, I can then create the new list from that template. I can then edit it to my heart's content, but starting with all the fields, rules, etc that I already built in the first version of the form.
The issue that I forgot to mention is that I need to then take this template from one SharePoint site and use it on another SharePoint site. InfoPath won't let me change the SharePoint List that the form submits to, since it is running just as a SharePoint List without being in a SharePoint Form Library. The SharePoint List data connections are grayed out for editing. :(
I can post the file, but since it is referencing another list for data population I'm not sure if you'll be able to open it or not.
Thanks,
Joy