You're correct in your assumption... I am talking about Windows Mobile (2003, 2nd edition).
I checked the registry key, and it's OK. However, when I click Publish, the files are not written to that location, only the recipe/list I first used to test. I even tried deleting & re-creating the folder then re-pointing BigOven to the folder, and the same thing happened.
I did notice that BigOven makes these folders read-only, even when I've changed that and emtied the folders.