Guia Roji is not very good. GPS is much better - especially Microsoft Streets & Trips 2013 even if just for maps and not GPS. But if all else fails go to the SCT websites where Guia Roji gets their maps and download the actual maps published by the Gov't instead of the cheap knock-off copies. Sometimes it can be difficult to find the SCT maps - and they update them every few years - not sure which link will take you to the most recent maps. They added the new roads a couple years ago - such as Arco Norte and maybe Devil's Backbone. These are like large 3' X 4' road maps but they are .pdf files you can download to your computer - each individual state in Mexico. Then use your computer to call up the state you are in and ZOOM the map for greater detail - use your cursor to move around the maps to find roads and towns. These are not the best but far better than Guia Roji and they are FREE to download. Streets & Trips is by far the best as it shows even the back streets in the towns and cities - for $30 - $40 one of the best buys on the planet for Mexico travelers. But if you want FREE find these maps somewhere on one of these SCT websites and download them. You will find them superior to Guia Roji.
http://www.sct.gob.mx/informacion-general/planeacion/cartografia/productos-cartograficos/atlas-por-entidad-federativa/listado-de-atlas
http://www.sct.gob.mx/informacion-general/planeacion/cartografia/mapa-por-estado/
http://www.sct.gob.mx/estadistica-y-cartografia/atlas-cartograficos/atlas-por-entidad-federativa/listado-de-atlas/
http://www.sct.gob.mx/informacion-general/planeacion/cartografia/mapa-por-estado/
http://www.sct.gob.mx/informacion-general/planeacion/cartografia/productos-cartograficos/atlas-por-entidad-federativa/listado-de-atlas
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