But at least you tried and they ate it! I swear it's the "magic" of WDW that makes everything taste sooo good!
So after doing a bit of conversions it seems as if 180 is 356ish or so in temperature (our recipe calls for 350). Is your non stick pan's finish dark gray/black in color? If so then you should drop the temperature a bit to 160 ish (160.2778 for those math people, who we all know I am not
) and that may help with the sticking. Also I always spray a non stick pan anyway and instead of the parchment (or grease proof) paper try aluminium foil as that won't stick...make sure you leave enough to hang over the end of the pan so it's easy to lift out.
EDIT: I just wanted to add that our local grocery store (ShopRite) has an International aisle and my DD found digestive biscuits; not the same as graham crackers, but yummy in their own right