I have drafted an applescript which I am using to export Omnifocus projects and tasks to Omnioutliner Professional, including the Context, Start Date, Due Date, Completion Date, Duration and Flagged columns.
No guarantees that it will work on your system, but it may be a useful reference, and you should be able to extend it to include any other columns that you may need.
Rob
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No guarantees that it will work on your system, but it may be a useful reference, and you should be able to extend it to include any other columns that you may need.
Rob
Download page