As for Dr. Gay's statements regarding the shape of the Universe, I believe she is mistaken. For my views regarding the shape of the Universe, see my thread entitled "The Shape of the Universe".

Co-moving distances are distances that would be fixed if the Unierse were not expanding. Suppose that the distance between some pair of galaxies would not be changing if the Universe were not expandinig. Actually, that distance IS increasing because the Universe is expanding. Those galaxies are said to be co-moving in terms of expansion of the Universe.