Run in turbo mode. (Shift click the green flag to turn on turbo mode then normal click the green flag to run) You can right click on the stage inside the editor to save a copy of the picture to a PNG file. Try changing the [set SYMMETRY (7)] at the start of the main script to alter the symmetry of the drawing. Fiddle with other values.
Takes the pen on a random walk with a fixed rotation between each step to create a sense of rotational symmetry. Each pixel is only drawn if it lies inside a circular window.