My daily SharePoint frustration - II

I was trying to create a custom list definition based on the discussion board thing. I was getting the error "One or more field types are not installed properly. Go to the list settings page to delete these fields." in SharePoint when trying to create a new item.
I was following the instructions from this MSDN article.
All posts I read were saying that my schema.xml file should refer to internal names. But I copied \FEATURES\DiscussionsList\Discuss\schema.xml , so if there were bad internal names it was SharePoint's fault, so I thought. It so happens that the problem was not related to internal names or escaping of space characters in internal names. It happened because I wasn't referring to the name of my custom list. (and I'm using a different BaseType)

Before:


After:



The error message didn't help me much either...