Hi Ed-
Thanks for the additional info. What I expect is the following:
1. You submit a document and it is named in the SharePoint form library as xxx-xxx-xxxx.xml (because your DBXLDocumentService submit data connection sets this as the DBXL::Name). Sounds like this is working correctly.
2. You export the documents, and then import them. (I believe the local file name after export does not matter.) Documents will get assigned a new DocID as they are imported, but the DBXL::Name should not change. That is, after import I would expect them to retain the same name (xxx-xxx-xxxx.xml) in the SharePoint form library (unless there are duplicates in DBXL::Name).
After import, try the following and then check the SharePoint form library:
a) reshred one document that was imported. This can be done via the DBXL Admin Tool. Does the name change from the DocID to xxx-xxx-xxxx.xml?
b) Submit a new document (in the location of the import). Does it get submitted with DocID as the name or xxx-xxx-xxxx.xml?
Thanks.