Not sure if T5 is the same as T6 and T7 but you can add a new location from the Map Files tab section on the right hand side, click on Add select Data locations. You can add a new location or remove a existing directory from the list.
I don't have T5 loaded on the computer at work so I will check tonight on my old laptop that is running T5 to see if the same option is there.
Delorme Products - Topo (5.0, 6.0, 7.0, 8.0, 9.0), PN-20, PN-40, PN-60SE,XMAP5.2, XMAP 6.2, Cache Register,InReach
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