I do not have the latest version of Power Tracks. I stopped updating at PT12 because I now use Realband (BIAB features on top of Power Tracks).
However the latest version of Realband still allows conversion of BIAB .pat files and Cakewalk .ins files. But the latest interface now includes this function under the Edit/Midi menu. I am pretty sure that Power Tracks probably has assumed this new layout also.
Since what you are doing has not worked for you, maybe this automated action might get it done.
Good luck.