Just don't check any box on that page
I reported that last weekend for Windows Desktop....so probably occurs in MACs too.
It Only occurs when the Personal Info, for the person being edited, has selected that they were in the military during 2017 on one of the prior pages.
I tell people that the workaround is to not check any box. (the error is probably sensing that the "Military" box was checked on a prior page, so that checking "None" doesn't compute....thus a programming error).
Doesn't happen in Online because the interview proceeds differently.