Hi Jan,
when I talk about the SD structure, I rely on Mio standalone GPS navigation, that also uses iGO SW upon Windows CE 5.0 OS.
First you need to boot in Windows GUI (not official LG SW GUI) by using special config file.
Then you put SD card with cracked image of iGo Primo (copy/paste files/dirs) in unit, and load iGO navigation directly from SD card.
Here we have a different situation, I guess Mazda connect (MZD connect marketing name in Europe) is first loaded, and it's main screen GUI with 5 icons: Music, Navigation, Settings, ...
In my opinion, overall Mazda connect SW should be cracked first, in order to use cracked iGO SW...
Mario