Dave, if the building is card, I would have thought the general purpose glue would have been a better bet. It dries more or less instantly.
If it's some sort of foam based, like polystyrene, then UHU POV is the stuff to use....It doesn't react with the foam like ordinary Gen.Purps. stuff does.
Mind you, you have nearly finished the build, so perhaps give it a whirl with the next building?
It all looks excellent. Really nice.
Ron