最终的答案是使用草稿格式的上载文档创建一个信封.然后将模板应用于信封的文档，而不是信封本身或使用复合模板.

The end answer was to create an envelope with the uploaded document in draft form. Then apply a template to the document of the envelope instead of to the envelope itself or using composite templates.

POST https://demo.docusign.net/restapi/v2/accounts/ACCTNMBR/envelopes/ENVELOPEID/documents/1/templates HTTP/1.1
Accept: application/json
Content-Type: application/json

{
  "documentTemplates": [{
    "documentId": "1",
    "templateId": "TEMPLATE_ID",
    "documentStartPage": "1",
    "documentEndPage": "15"
  }]
}