A roof collateral load rating of "0" means the frame was not engineered to carry the extra suspended weight of a ceiling, risking sag or failure without reinforcement. Can you do it? Sure. Will it fall down? Maybe, maybe not. Is it advisable? No. Per the spec sheet, the building was not designed to carry the load of a ceiling, which is typical of that method of construction (tubular steel, "carport-type" buildings).
At this point, working with what you have, I'd look toward spray foaming the underside of the roof.