Hey Fot, wow, sorry to hear you had so many problems. The door is easily popped open with a piece of rubber or silicone. Granted, that shouldn't be like that, but we have found an easy workaround.
Also what
batteries did you get? Did you get the kit or just the device, because my batteries from the kit fit perfectly. Oh and I love the bottom that rocks. Mine never falls over. Did you have a
tank or something heavy on? I use a huge EMDCC and big heavy metal driptip, but it still doesn't fall over.
Surely you noticed that it rocks before you bought it....?