First 250g I'm seeing with heated seats...nice ride bro...
And whats wheel air balancing?
About the screen, what do you see on it when you switch on the car? Some message in japanese or map screen?
If you see message in japanese, then you need to insert mark x navigation dvd in it and only then the navigation system will start functioning.
About the video, you need a dvd changer + video card for that...video card is not that expensive...around 2-3ks.
I have an avt 6 disc dvd changer including remote control and all other accessories / cables, for your mark x...slightly used...I can give it to you...