@Gjon
Could you post a shot of the screen More.../Help/About, which give informations about your Primo version,... and possibly the GPS model on which it is run in order to better understand your configuration

Primo has three customization possibilities, either by a skin stored in "content\skin", some zip in folder \ux, and the branding.zip, if none of the three is used on your device it may have some capacity to take unrelated captures to navigation software

@Boki
Why maximize it? Igo would have to be in fullscreen mode.
I occasionally use primo on a Wince GPS which has a physical button allowing me to return to the main menu of the device to adjust , the sound, brightness and various other parameters independently of primo, in this case primo disappears of the display by "minimizing", to return to primo in maximized screen I press the button associated with launching navigation, there is nothing surprising in the fact that Gjon's GPS could have such a device, which is why we need him to give more details in the case where his device runs well under Wince and not on android.