did your cyser ferment all the way out before you campden'd it? if not, then the yeast will eat the priming sugar as well as all the other sugar in the bottle, resulting in over-carbed cyser, or perhaps even bottle bombs. If you got the cyser down to terminal gravity first, then you should be fine.
Primary:Russian River Redemption clone, Kelly's Melomel, Graham's English Cider 22-23
Aging:Public House Dry Stout, Procrastination Porter, Mr. Brown Ale, Westvleteren 12 Clone, Mead, Duvel Clone, Graham's English Cider 6-21, Belgian Draak Strong Ale, Fig Melomel, Acerglyn, Restorative Tonic Metheglyn