Actually... it worked great but also deleted the sides in the centre piece. I can and have fixed it easy enough but thought I would see if it was caused by something else i can do better.

you just coined a new phrase Thanks works great.

Hi Fredo, great Extn. Im very beginner. Im getting a failure (me?). This object is 22mm diameter - hopefully the images speak clearer than I can. Im trying to round off edges highlighted in image below but to do so results in fill in or some other failure see other .jpg. Any ideas?

You can see in the image with green ticks it worked on a couple of edges. It works if I only select 1 or a couple of edges.