We discuss the moduli space singularities that are generally present in
five-dimensional vector-coupled supergravity on a spactime of the form R4 x
S1/Z2, with vector fields surviving on the Z2 fixed planes. The framework of
supergravity is necessarily ambiguous when it comes to the non-singular
embedding theory, so we focus on those models coming from Calabi-Yau
three-folds with wrapped membranes.Comment: 13 p