Using Drupal 7.41 and workflow 7.x-2.8, when you attach fields to a Workflow, the fields do not get saved with the workflow field.
It's easy to replicate: Create a workflow, add a field to that workflow in admin/config/workflow/workflow/manage/workflowname/fields (ex: field_confirm), attach a workflow field to a node type (ex: article, I'm using workflowfield here), create an article and set a workflow state & comment. Upon saving the article, the workflow state and comment get saved (see workflow tab) but no field_confirm data gets saved or displayed. The data is not in the database either - the table field_data_field_confirm / field_revision_field_confirm remains empty.
Is that feature not ready yet? Or am I missing something? I tried with workflownode and it didn't seem to work either.