To define pages we currently require two fields to be present: title and path. The fields are used not only in the dashboard but also to determine the file name of the page. For now these are not automatically added so they'll need to be defined manually:

alinea.type('My type', {
  title: alinea.title('Title', {width: 0.5}),
  path: alinea.path('Path', {width: 0.5}),
  // ... other fields