an example can be found on AMOSPro_Examples:Examples/H-3/Help_34.AMOS
OPENs a new AMOS SCREEN on the display.
Screen Open number,width,height,colours,mode
number ranges from 0 to 7.
width and height set the size of the screen in pixels.
colours enter the number of colours to be used.
mode sets the screen mode. Allowable options include Lowres,Hires, and Laced.