Hi Edward Clarke,
are you a customer or a partner? If you are a customer, I suggest speaking to your partner about a personalized training using your process as an example.
If you are a partner, you should get the DSC training or ask someone in your company who already did that for help, as this also uses invoice processing as an example.
All the functionality is documented in the Knowledge Center, Knowledge base and Partner Portal, but learning how to use that best is something you have to do for yourself or with the help of your DW Partner/DW Academy/DW Professional Services.
Greetings from Germany,
Simon H. Hellmann
DocuWare System Consultant