With DocuWare 7.1 you can insert data in to a Form using a workflow. First of all you must create a merge form. The target field must be a fillable area of the PDF. Note that the area cannot be a target field from the form submission. So you cannot replace data you can only add data.
When creating the workflow, your trigger must be by "Submission of a form".
Phil Robson
Senior Director Client Services, Americas