High humidity environments should reduce oven temp to 150 and bake an additional 2 hours. The way to test this is the first time you make them… take 2-3 nuts out at each 30 minute increment after the initial 2 ½ hours. You have to let them sit for at least 3 hours before being able to tell if they are going to crisp up. Sometimes this takes up to 24 hours depending on the humidity level. Don't be afraid to leave them out to crisp up. From what I can tell, this has a lot to do with not using actual sugar in the recipe.