The behavior in Ultiboard 14 is intended. The format has been updated to to follow the Excellon standard fromat, where the decimal points are implicitly defined. So in a sense, it is actually the drill file in Ultiboard 13 that is corrupt.
We are having the same problem with 14.0 if you change your output to mm then it will output the files correctly. There seems to be a scaling issue with the inches output for NC drill