Klaus, thank-you very much. Some of what you say I was already aware of (the problems), but hadn't yet figured out how to fix it. I had already tried to fix point #6 but had failed. I will do as you suggest. You have also touched on something else that I have been struggling with, being the inconvenient confusion of dip and no dip. I have been trying to get past my confusion with that, so you have helped. The buttons on the panel is something I knew that I would eventually get to, but hadn't bothered to this point.
Moving code into Designer Scripts is something I had seen, but is new for me to work with. That will be new knowledge for me.
I am very grateful for your help and, as I have said in a previous post, hope to be able to help others at some stage in the future in a similar way.