I would not say this is resolved.
I am having the same issue as the above two posters. The instructions provided by Justin only seem to change how you reference the field later on within Ninja Forms (ie. {field:<admin-label>}. The input itself still has a name formatted like nf-field-#.
This is preventing me from integrating with the tracking code for the CRM one of my clients is using, which requires the input field to have a specific name so it can change it via javascript.