Big-Shot is correct. 3490, 359x, 259x etc [the 2012 & 2013 nuvi series] use the exact same files so no need to 'adapt' them, the 3597 files will work in all. Just copy & paste to correct folder. Remove old files remaining from previous map versions. Note: Although the 2012 and 2013 series use different TTS voice files, the Automatic Speech Recognition files are common to both.
Those files in Post #6 are the map-related files for this version. To enable different languages for speech recognition, you also need to have the correct *.srd file in the unit's .System/ASR folder [srd files must remain in unit memory, other ASR files can go in a separate ASR folder in the microSD's Garmin folder if you want to save space on the unit]. For example if you want to use AU English voices Karen and Lee, you must have en_AU.srd on your unit. Or en_GB.srd, en_US.srd for the corresponding TTS British/UK and US voices. Same with Spanish, es_ES.srd and es_US.srd etc. These are not required to be changed with each map version as are the map-related files, but you should dl the latest versions using WebUpdater or GarminExpress. My NA 3597 is not offered any Portuguese SRD files though.