[Geoff Bacon]

Thanks for the info; I now realize that a duplicate only applies if the file is binary identical to an existing file at the expected location.

I am more interested in performing the equivalent of a "swap file" should it identify a conflict (which it hardly ever does)

I have the following Storage options checked:-
* Let MS Manage my files
* Expose MS Storage Location
* Delete Original After Copy

The other items are unchecked i.e. no "Add Unique Id" and no "Create Subdirectories".
Note: When I first started I did have "Create SubDirectories" checked but I unchecked it about a week after purchase. I don't believe I have ever set/reset "Add Unique Id" 

I'm not changing the settings between imports.
If I import the same song twice in two separate Batch Imports, one after the other, I get two entries in the database.
When I look at the files for these entries, they both display the same file name (when editing the song)

I would have expected the conflict screen to be displayed (Note: I have always had this behaviour)

"Settings/Find Missing Files" shows no issues

I hope this helps you find the problem.

Geoff