I would recommend people stay well away from Channel Advisor pro in the UK. The customer support is non existent, even when there are serious problems, ie the system is no longer loading items in my ebay shop, it still takes them about 14 days to reply, if they even bother. The only way to contact support is through a form on the web based system, there is no phone option even when an issue is serious and urgent.
There are no setup instructions to speak of, and it is clear that the system is not yet fully tested or ready for use.
It is a great shame, because this could be a really good tool, but it needs a lot more work and responsive customer support if it is to be of any use.