without testing, i guess this is your problem:
var myFolder = Folder("trans/9780630/983660/Linked/");
var new_path = myFolder+ '/'
your new path becomes: trans/9780630/983660/Linked//
fix: either var myFolder = Folder("trans/9780630/983660/Linked");
or use myFolder insead of new_path everywhere in your script.