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Your wishlist can't be fulfilled with your current setup. You need to transfer your charts to a Chart sheet. Find instructions here.
I have read a lot about the subject while doing my reasearch on this answer. Many, if not most, people recommend a "Dashboard" to be created with embedded charts, avoiding a Chart sheet. Following that advice has cost me a lot of time. Pellier (the author of the article at the above link) is a renown VBA specialist at Microsoft and beyond. He takes a completely different approach by saying, in effect, "put charts on a Chart sheet".
This seems to be because the Chart sheet has some functionality a normal worksheet doesn't have. First among these are Chart events which I painstakingly installed in your worksheet in my last answer. The point where I got stuck now is to define a group of charts, any one of which might have been clicked. It might still be possible with your current setup but when you use a Chart sheet it's standard fare.