Greg, about a year ago I purchased a BR G-1 from Charles at HPA, and it had the same zipper problem as yours. Charles told me to take a long nose pliers and very gently tighten up the slider on each side, but using a very light hand. It worked. Take a good look at it first as it could be too tight in which case you need to pry it apart a little with a screwdriver. Hope this helps. Don't you dare size down.