"Hi Michael and Prakash, Thanks both for your input. I solved the problem by making giving each image in the circle an opaque hotspot link..."

"Hi Alexandros, Thanks for your reply and apologies for my tardy response. Work gets hectic from time to time. I will test out your sugges..."

"HI, After further investigation it appears that the error arises because of a Moodle authentication conflict but if so I would not expect..."

"Hi Michael, Thanks for your solution. Works a treat. My layer contains a number of images which students need to have time to review and ..."