Hi @RobinSlee , I am not sure how applicable this is, but a couple of years ago I created a deck of illustrated playing cards based on the original Peter Pan book by JM Barrie. Even though the book falls into public domain, I had to be really careful because of Disney. In my research I found that as long as my illustrations/product was based solely on the work of JM Barrie and was not influenced by the Disney creations I would be ok. Disney actually licensed the property so they have those rights for their IP in that regard, but others can still use what falls under the public domain.
The project funded on Kickstarter for over $28k, so this of course could have been contested had the wrong person seen it, but fortunately it was not. Here's a link if you want to check it out: https://www.kickstarter.com/projects/370388468/neverland-bicycle-playing-cards