I think you should check it again because it is working with me. In sample 2 where you have mentioned  (2) here am getting 10+c instead of b+c 

wel I don't have much idea about this and i tried to open your file but i can't see your work. I recommend you to reinstall maple but I am not sure this will help you or not. Further you can contact support@maplesoft.com for any error related to maple product 

yeah that i got i have to use maple 15 but can you help me for its code how to code that in maple for this pde