Options now showing if “Show in categories” is selected

Hi, I just started with the YITH WooCommerce Product Add-Ons plugin (free version). Overall I’m loving it, however If I choose the option to “Show this block of options in: Specific products or categories,” it does not work for the categories. It will only show up automatically if I type in the name of the product in the “Show in products:” section, but not if I put the category of all of them in the “Show in categories” section.

If I add it to all products in a category, the options will only show up if the product is a variable product AND if the customer has chosen a choice (in this case, large or small) which especially does not work if the product does not have size options.

To see an example of all of this, I currently have some options for a hidden category of book boxes (added to the “Show in categories” section), which should mean all the book boxes in the store should have these options showing. However, this product is the only one that I did not list in the “Show in products” section as well, the options do not show up until you pick a size, like on this page: https://www.nerdfelt.net/product/clever-girl-book-box/

However, this other page I listed in the “Show in products” section as well as the “Show in categories” section, and all of the options show up immediately upon loading the page. https://www.nerdfelt.net/product/dnd-club-book-box/

I hope all of that makes sense, and I hope this can be fixed fairly quickly. Thanks!