Here is a sample code to achieve this, not perfect
but should get you started.

Code:

---

var speed = 2;  // play with 2

action myEntity
{
  while(my)
  {
     my.x += sign(screen_size.y/2 - mouse_cursor.y) * speed * time_step;
     my.y += sign(screen_size.x/2 - mouse_cursor.x) * speed * time_step;
     wait(1);
  }
}

function main()
{
   ....
   ....
   mouse_mode = 1;
}

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