Cannot Edit Form

Purchased XI Pro with the single purpose of creating forms.  Once created in Forms Central and 'Save a PDF Form' I cannot edit in Adobe XI Pro,  When I select Forms/Edit I get the message to 'Save As Copy...' I do that then get a screen that says 'You cannot edit this as a form.'   I can't do any of the neat features those nice video in the Adobe site says you can do.  Appreciate any advise.