v4.1.21 is now generally available; it includes the following fixes and enhancements:
Shell
- New SharePoint DataSet command now available in QTAssistant Shell as well as QTAssistant Query Designer.
SharePoint:
- Ability to infer relationships between lists based on LOOKUP for single value fields.
- Extracting metamodels from MOSS 2007 lists is broken.
QXSD:
- New UI Layout.