For legal reasons one need to specify the taxes on the generated invoices. DTRegister does specify it in the first place, but DTInvoice doesn't. ("Forgets to copy it")
How can I configure this? (It should work without any manual actions in DTInvoice, because they are generated and sent automatically upon initiation of DTRegister)
Looking at the template file for the PDF invoice this appears not to be included at all, otherwise I would have assumed I had missed a setting somewhere.