There is a public web service to convert Your SAP WF definition (exported in BPML from your Workflow builder) into an editable BPMN note.
Easy-to-use tool gives you the opportunity to design changes to your workflow processes, discuss them with key users or just document your workflows in a business-user understandable way.
You may want to check it out, if you ever found yourself in the need of working with an old and forgotten WF, one you did not create, or just design-in some new processes, and had problems getting one's bearings..