Is there a reason you didn’t ask for support in the Support forum prior to leaving a negative review? I would be happy to help you figure out why it isn’t working for you, because I can assure you that the plugin works.
If you’ve tried deactivating all the plugins then we can safely assume that your theme is the problem. Please read the FAQ. You can ask your theme’s author to patch the theme or follow the instructions to try to patch it yourself. Or in the worst case follow work around #1, which is not ideal but requires no coding.
Also of note, the Nav Menu Roles fields do not appear in the WordPress customizer as there is literally no way to do that with the current state of WordPress, the menus must be modified from the admin in order to use NMR.