[Zope-CMF] Problem with import/export and workflow, from Linux to Windows

[Sheila María]

Hello!
     I continue with my small fight with Zope, Plone,..When I wanted
to export/import my PCNG(tracker), this action give the state
"pending" to all the issues!!!!
     I've created an External Method with:

    def EMRestaurarEstadoIncidencias(self):
        old_wf = 'pcng_issue_workflow'
        for issue in self.objectValues('PloneIssueNG'):
             H = issue.workflow_history
             if H.has_key(old_wf):
                  issue.status = H[old_wf].pop(-1)

but I have no answer. 
     I don't know how I can accede to the "status" of the issue, with
the purpose of returning the last value to him of its workflow's
history. I've included all the "imports" needed.

        Sorry, but could you help me with this???

                                        Thank you very much!!!!