I try to set the picture but that darn blue outline square thingy keeps cropping them and only in the centre of the screen so that parts of the picture i want are erased.
How do i crop the picture where i want and set as wallpaper?

it's probably the way you have set it up. When setting up your custom background picture, you should see a drop-down box at bottom-left called "Picture position". Click this box and choose either "Fill" or "Stretch".
Click "Save changes".
