The new interface contains all the same options and functions but shown in a more user-friendly way. Here is the guide that will help you to understand it.
To activate/deactivate the new category editor interface go to the "Global Settings" and flag/unflag the checkbox.
Now when you create the new customization new interface will appear.
First, you will need to select the type of customizations that are now separated into categories. For simple customizations, you can now choose the way it will be displayed.
Scroll down and you will be available to set conditional logic for the category.
Next, there is a field to add a category description and filed for the class name.
Next, you can set cart and quantity behaviour. In this dropdown, you can set if this category is required on Add to Cart, hide category layers in the cart image. Set quantity multiplier source or exact value.
In options behaviour, you can set deselect of the options, synchronize options by the label, and also set conditions for clearing other categories.
Next, you will see the options editor. By default, there are three options. You can add or remove them. Also, it is possible to set label, price, value and connect options from SKU without getting to the Option Edit screen. Other options are available on the Option Edit screen.
Option Edit screen
Click on the Edit option to get to this screen. First, you can upload the image for the option.
Lower on this page, you can set Label for synchronization, set values of the option such as Price, weight, additional quantity multiplier and connect option to the existing SKU from your inventory.
last you can set the conditional logic for the option and add the description for it. Don't forget to save Customization.