Igor, that's extremely helpful, thank you.
But since I raised this question another issue has arisen, the piece of code for making images expand to fit has stopped working. See separate query. Do we need to fix this first?
Also will I be able to see what I need to do from your example?
Finally there are two apps, both of which are shared with Appery support references: projects/60288fe2-1325-4512-8ac9-36dd77d3ccce and
projects/4a60a416-7b93-4743-b2ea-abd82a259660.
I'm much encouraged by your support
Dan