Only way for you to get a high resolution image is to open the reconstructed baseTiles and reliefTiles in preferably a graphics editing app.
I'm looking at NWO and your in luck they left a blank map image (reconstructed baseTiles) named NWOblank.png in the map folder located in new_world_order-master.zip folder.
You can paint it and scale it, as you see fit and print it. And or you can add the reliefTiles over it and have one of the available map skins. Note you will still have to paint the blank.
If you want info on reconstructing the reliefTiles. You can ask for help here.