My workflow is launched with the submission of a PDF rendered from an XDP. Files attached to the form are gone at the next step. I have tried selecting "Copy All Notes and Attachments From Previous Task" as listed here:
http://livedocs.adobe.com/livecycle/8.2/wb_help/wwhelp/wwhimpl/common/html/wwhelp.htm?context=Workbe... , but it did not work. That seems to relate to attachments to the workflow.