Does this customer has issues with wrong PDFs (from another company/contact) attached while sending emails via maintenance "create open invoice customer statement".
It sounds very similar to that.
Try to debug FormLinkDocumentFileNames().
I would like to know what BackgroundHALShouldPause does, and how to use it. While it's listed in the HAL Primitives report, it is not used in source code and it doesn't appear in the LMS HAL...
