you'll need to fist load your image up.
//in system.vc
int imageToDraw=loadImage("imagename.jpg");
Next create a function to draw the image like so:
//in system.vc
void drawOnScreen()
{
TBlitlucent(60,200,0,imageToDraw,screen);
}
finally in the first function of your map code,
//in map.vc
void onLoad()
{
hookRetrace("drawOnScreen");
//load the player and whatever else
}
and that'll draw the image to the screen every retrace.