I think you are right in thinking that the craftsmanship is lacking.The manufacturer should have thought about the changes in climatic conditions and also the wood movement.He is just trying to brush you off and I feel all are pleas of an exchange or a refund are going to fall on deaf ears.You will have to really try hard or maybe ask for repairs.Well! best of luck.Do at least once try and talk to the manufacturer,maybe ,you will be able to convince him and make him understand your view point.