When installing a map directly from a “computer based” TripleA/Java the downloaded maps as well as the savegames are stored in a folder c:\Users"User"\triplea\…
You can easily verify this and/or access this directory using the TripleA “Open User Maps and Savegames Folder” button that is accessible via the “Engine Preferences” button in the starting dialogue.
From the stick installation - as mentioned above - you will find the downloads and savegames here:
Stick/PortableApps/JavaPortableLauncher/Data/AppData/triplea/
You can easily verify this and/or access this directory using the TripleA “Open User Maps and Savegames Folder” button that is accessible via the “Engine Preferences” button in the starting dialogue, too.
Your problems sound like download errors. I would recommend to delete the maybe corrupt data from the above mentioned folders and try again.
You can of course download the map.zip directly from sourceforge and place them in any of the maps-folder:
As well in Stick/PortableApps/JavaPortableLauncher/Data/AppData/triplea/maps/
or in Stick/PortableApps/triplea_1_6_1_4/maps/
Sidenote: The *.properties file is used to compare the map version installed with the map version provided via the triplea_maps.xml when using the built-in map downloader.