Are you looking for the custom menu settings in the Menu Customizer? If so, WordPress does not support any custom fields there yet and there is nothing I can do until they do. You must edit the NMR fields in the admin menu editor. I can confirm that it works in the admin side in WordPress 4.3.
Have you read the FAQ? It it possible that you have a conflict with another plugin.
It conflicted with Shape5 Vertex theme, not WordPress. I am using 4.3.1 and if I disable the template (as the work around in the FAQ stated) then re-enable the template, it works just fine.
I prefer to say that the theme is conflicting with Nav Menu Roles, because I don’t think theme’s have much business modifying the admin menu walker. 🙂 If you refer back to the FAQ, you can patch your theme or request that the theme author patch the theme to be compatible. It’s only one line of code.
