Thank you, Support, for your prompt response.
Yes, I am able to do the function you ask about--"Save a copy of this attachment to a file," wherein I re-copy the document to my computer (to a different location than where I had it scanned and then linked to HealthFrame). Nevertheless, it still won't open from within HealthFrame.
This is all ok for my personal use, but I am trying to understand how to use HealthFrame in the most useful way for my doctor to access (such as via a USB flash drive?).