Just to be clear, here in the labs on our four different Windows Mobile devices, it does not require a soft reset. The shopping list transfers successfully and can be read by the program. At the present time, we cannot replicate this behavior you're reporting, but we certainly believe it's happening, and are suggesting one thing to try. (Unfortunately, the large number of Windows Mobile devices seem to have slight variations between them in how their firmware implements file handling -- one would think if it works well in the emulator and on four devices it'd work on all machines.) One user who reported the same behavior found that a one-time soft reset cleared up the issue.
One other issue could be the shopping list data itself -- does this happen for even a very small list? E.g., one simple item on the list?
We will investigate this issue further for the free Windows Mobile Companion, but until we are able to fully replicate it here, we don't have any anticipated schedule for you on this... sorry!