Hi, I'm in China working in a kindergarten and last year they wanted me to make a gingerbread house for them. Actually I had never made one before as I come from NZ and it isn't really a tradition for us. However first I made a small house to test things out and one of them was using different candies for the windows. I found using hard boiled candies worked best and gave a fairly realistic effect of an old fashioned stained glass window. I did end up with some mixed results in the final house though with some of the windows melting, but that was only after a month, however after 3 months all the windows had melted. I did find that the windows in the pieces of gingerbread that were slightly overcooked, in other words cooked at a higher temperature, lasted longer.