in working with NEA, we have found that their checkboxes are not compatible with Responsive projects. The source file, always in word, has checkboxes made with symbols and content controls. We can bring in checkboxes manually within the project, but this would still cause an elaborate amount of work on the client end since they would still have to check the boxes manually post export.
Please look into ways to improve checkbox functionality - specifically for NEA and other clients, as this is very frequently seen.