If I completed the PTD, does this seal or expunge the record and do I answer yes to a question regarding if I was placed on probation during a criminal proceeding?

You would actually have to seal or expunge the charge itself, Pretrial Diversion does not automatically seal or expunge the charge.  My firm does handle sealing or expunging charges and would be more than happy to offer you a case consultation concerning the charge.  Pretrial Diversion is not probation.