He recommended this stool and said I couldn't have a gym ball to sit on (due to work accidents) and then got me to move my telephone to the left hand side of the desk. He also replaced the chairs for everyone else in the office. Result!
I am now therefore ergonomically sound and set up! The stool is quite comfy, but takes some getting used to and it does make me sit up straighter :-)
I am glad it is Friday, and after a fairly productive day, I did some paper shuffling, tidying, recycling and then went home!