The member list displayed does not appear to consider current child elements of the context element when assembling the list.
For example, I would expect that an xsd:sequence containing ElementA, ElementB, ElementC and ElementD should only populate the member list with appropriate element for it's current position within existing child elements.
Same too for xsd:choice lists where @maxOccurs = 1. If one of the choices is already present as a child of the context element, none of the other elements should be presented in the member list.
Please let me know if any of this is unclear (or if you simply disagree ;)). The problem does not occur in the WPF sample project.