Here the results:
1) D3048030A.jcv works with 3790T. The correct folder in sdcard is \GARMIN\JCV
2) NTU correctly compiles and uploads via mapsource (map unlocked by Garmin keygen v.1.5) , but 3790T is unable to authenticate the map. Unlocking with Fast IMG unlocker v2.1 loses some search capability (searching for Milano, returns Milano 3, Milano Marittima, and others, but not Milano, MI). I'm trying to sorting this as I write.
3) ASR-SRX must be saved into DeviceLetter:\.System\ASR and not "Garmin folder in the ASR Folder" as described [Only registered and activated users can see links. ]
4) gmap3d.img correctly works when unlocked with Fast IMG Unlocker v.2.1 and saved into sdcard \MAP
5) G2S Path: \.System\G2S and .db Path: "\.System\SQLite\" as correctly described