well edge wouldnt copy all external files that you added to your project in to publishing folder, you should doing copy paste your files and folders created by your self after published !!
and i cant undrestand "Unlike you, I am not that skilled and frequently make mistakes that render some of my new code attempts totally unusable." you can save your project everytime with new name to have your previews works !!
and about removing your symbols that uses class name, you are doing wrong, you should doing this way
sym.$(".Preview").remove();
and thats why you cant get it to work
if tehre is any question feel free to ask me 
Zaxist