Re-Attaching Sublists to Custom Form

We have a custom form (customized from NetSuite Standard Project Form) called Project Form.  We created a 'copy' of this form using save as under another name.  Short Form.  We disconnected all subtabs and sublists from this form.  The sponsor asked that we re-add the sublists back into the form.  We went into the form and reselected all the subtabs and sublists, however the sublists do not show.  The field used in the sublists filter is no longer available to choose.  Has anyone run into a scenario similar to this, where the subtabs and sublists were attached to the project;