If you are LDS, you have to have a temple recommend, and if not, you have to essentially live like you have one (referring to behaviors, not beliefs).

That is determined/verified by the applicant's bishop, not by the GA. I don't know for sure what the GA interview covers, but I would guess it's more about the mission and purpose of BYU, and the LDS church's involvement in the university. Or something along those lines.