I don’t know if it’s too late, but I too wanted the Scenes to not be automatically dismissed when I selected one. After consulting with Ron, I just made a separate Scenes Page with the 8 scene buttons on it. It also includes a “back” button which returns me to the page I was on before I went to Scenes. I set up my Main Page scene buttons “hold” function to flip to the Scenes page.
All of this is for my GT16, so I’m afraid posting the file won’t help you much. Very easy to program yourself.
EDIT: I can use my laptop (instead of this iPhone) to provide a grab of my Scenes Page if you like.