Last year I designed a form (to PDF) within Adobe LiveCycle Designer (latest version). Now I'v upgraded to Adobe CC, but I don't find this programm. Instead I've got FormsCentral. How can I import this special PDF form into FormsCentral and keeping the filling-fields, buttons, etc. ?
Adobe LiveCycle Designer and FormsCentral are two separate products. FormsCentral currently supports Static XFA forms, not Dynamic XFA forms.
For more details let me point you to the FAQ page: http://forums.adobe.com/docs/DOC-4275. Please take a look a this page and if you still have questions, do write back.