I now believe that William Pyper is William Hastings/Hasten born/christened @ New Deer 12/9/1793. The census records for William Pyper state he was born @ New Deer.
I have no explanation for the name change, however if they are the same person his father is Joseph Hasten and his mother is Janet Pyper. They have a number of other children at least one of whom is named Hasten in the OPR's but in the later statutory registers is Hasting(s)
The data in the IGI which gives his parents as Pyper and Cruickshank is , in my opinon, incorrect.