Our team within Microsoft Global Business Support that supports developer writing Windows Store apps and Windows Phone apps have a team blog here. This is multi-contributor blog that offers advice and ideas on solving some of the common scenarios that our support teams see customers trying to work through.
One of the areas that is new for many developers of apps for Windows 8 that are made available via the Windows Store is the certification and publishing process. Here are some resources that may be useful for that:
Index of UX guidelines: The index of UX guidelines is the checklist used to evaluate apps in the App Fast Track.
Certification Requirements The formal list if requirements your app has to meet. This is a “living document” that gets updated and has release history notes at the bottom. Note that a recent addition (6.12) is that if you say your app meets accessibility requirements then it has to actually meet the baseline set of requirements. To learn more about Microsoft and accessibility check here. We also have accessibility centre for developers here.
Avoiding common certification failures Driven by the app certification team, this new topic lists common reasons why apps fail certification.
Resolving certification failures This article contains an entry for each certification requirement, and lists the current recommendations for resolving common failures.