I agree that there is an issue with the Scripting Index - the way I look at the code is that in one you get a handle to the Picture Box object and in the other you get a handle to the image. So rotating the image doesn't matter until you then display it as you showed.
If you put a "Wait (1);" in @txnelson code before the "pb << rotate left;" line, you will see the image displayed and then rotated in place.
Thanks for your answers - not something I have tripped over yet, but would have soon!