Hi Renee,
In a case like this, when it states you can not change or modify the main product (in this case the book itself) what you can do is create your own promo, with what ever graphics you want to use, you can even create a new extra book cover to promote the book, just don’t change the main product cover, (sell the book as is with original cover)
You are allowed to create and brand your own sales letter, (not the product) so you can target what ever age audience you like. I hope this helps.
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