NEW UK Consumer Law
"Digital content rights The new legislation sets out – for the first time – your rights when you purchase digital content. As with all products, it must be as described, even if the software is supplied free, as might happen with a laptop. If the digital content fails, or is not as described, the new rights will be enforceable against the retailer – such as Google, Apple, or the software provider – rather than the developer. The retailer will have to compensate you if any device, or other digital content, is damaged as a result of the digital download. It would also be liable to pay compensation for removing a virus."
This is just a heads up for the UK base people here. You have probably heard about these new laws. Basically if you but for example a plugin and it does not work. You are entitled to a full refund. The onus is on the software provider which is Appthemes. Remember all software is brought through the Marketplace, therefore they are the provider. They have to give you a refund. There is no room for them to say you need to contact the developer etc. They would give you there refund then they take it up with the developer.