Cannot add resources

When attempting to add any of the subject items (equipment, location, or resources), the following error is generated:
Exception

KeyError: 'add'

Traceback

File "/usr/lib/python2.7/dist-packages/zope/publisher/publish.py", line 132, in publish
  result = publication.callObject(request, obj)
File "/usr/lib/python2.7/dist-packages/zope/app/publication/zopepublication.py", line 207, in callObject
  return mapply(ob, request.getPositionalArguments(), request)
File "/usr/lib/python2.7/dist-packages/zope/publisher/publish.py", line 107, in mapply
  return debug_call(obj, args)
Extra information: <schooltool.skin.flourish.zcml_content.FlourishResourceAddView_addResource.html object at 0x88cabd0>
File "/usr/lib/python2.7/dist-packages/zope/publisher/publish.py", line 113, in debug_call
  return obj(*args)
File "/usr/lib/python2.7/dist-packages/schooltool/skin/flourish/page.py", line 67, in __call__
  self.update()
File "/usr/lib/python2.7/dist-packages/schooltool/skin/flourish/form.py", line 72, in update
  super(AddForm, self).update()
File "/usr/lib/python2.7/dist-packages/schooltool/skin/flourish/form.py", line 56, in update
  super(Form, self).update()
File "/usr/lib/python2.7/dist-packages/schooltool/resource/browser/resource.py", line 610, in update
  self.updateActions()
File "/usr/lib/python2.7/dist-packages/schooltool/skin/flourish/form.py", line 59, in updateActions
  super(Form, self).updateActions()
File "/usr/lib/python2.7/dist-packages/schooltool/resource/browser/resource.py", line 583, in updateActions
  self.actions['add'].addClass('button-ok')
File "/usr/lib/python2.7/dist-packages/z3c/form/util.py", line 188, in __getitem__
  return self._data[name]

 There is no workaround that I can see and clearly this is a significant problem.