I have not tried this myself but I would imagine that if you import your PDF in FormsCentral and you arrange the columns in the same order as your columns in your old Response file you might be able to copy and paste your data from the Tracker in Acrobat into the FormsCentral table. If that doesn't work I would try to export as Excel and copy and paste from Excel into FormsCentral. Copy and paste from your CVS won't work though.
Let me know if it works to copy and paste from tracker or excel.
Gen