Wedding In A Few Days

I have bought a rather expensive dress to go to a wedding in switzaland as it is a afternoon wedding i have gone more for the evening look in way of a backless dress (prob not the best chioce but!) anyway it has a slight train on it so is in the menders as we speak and the lady is going to attach a ring of material so i can lift it from the floor when walking. The dilema i have is i need something to cover me in the church and keep me warm is a pasmina ging to be ok?
Also the dress is a kinda beige colour is this too light for a wedding?? I did show the bride and she said it is fine?? need advise asap..