This will not extrude....

 From:  Edwin (EDWINTSI)
1393.4 
If you look at shot1, the selected points, when i zoom in real close you can see the upper points are NOT connected.
I don't have the time to test it out for you (sorry) but maybe welding (trim/weld) the points will solve your prob.
As a final touch, God created the Dutch
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