I have a TT XL that came with a "USA & Canada" map. I recently purchased the UK & Ireland map from TT, and before installing it on the XL I used TT Home to move the USA & Canada map to my computer (an iMac) to make room on the device. I can see the USA & Canada files in Finder. I now want to put the USA & Canada map back on the device, so I removed the UK & Ireland map from the device. When I try to "Install Item from Computer" using TT Home, it only offers the UK & Ireland map - it doesn't seem to see the USA & Canada map on the computer. What can I do to get the USA & Canada map back on the device?