I think the problem here is that rather than being given a complete list of reasons for failure each time, they're only being told about one problem each time they submit and fail. So, instead of being able to just fix all the issues in one shot, resubmit, and then get in, they're having to submit over and over again!
Now sure, there is clearly a question of whether the guys making the app have done their homework properley, and haven't made themselves fully aware of all the requirements to pass the approval process - nevertheless, it seems that Microsoft could be a little more helpful here in communicating the reasons why an app fails.
Given the sheer number of apps that I see appearing in the 'new' list in the marketplace that are -frankly- just spam, It's disheartening to see a decent looking app like this fail to get through.
I hope the Microsoft guys that are in touch with Carbon can help them get their app through.