Not sure I understand the question. Are you talking about the "Download Response as PDF" feature (to see the PDF filled out with the filler's data) or the "Download Submission Enabled PDF" (to sent to people to fill out)?
If you imported a PDF in FormsCentral, the Submission Enabled PDF will look exactly the same as the imported PDF plus a submit button
If you designed the form in FormsCentral and save the Submission Enabled PDF it will look very similar to the web form (switch the view in the Design Tab to Page View to see what the PDF will look like)
The PDF doesn't use skip logic or show/hide logic so this mean that the PDF always shows all the form elements
I answered a similar question today. See http://forums.adobe.com/thread/1251981