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I was able to reproduce the problem when selecting "Auto Collect". However the second option is fine. Maybe because the imported PDF form isn't supported with Auto Collect because it does not have fillable fields? I'm not quite sure about this so I have raised this to our developers for further investigation. They'll get back to you with more information about this error.
Screencast showing the error: https://shots.jotform.com/elton/2015-04-02_07-03-49.mp4