Do you have the full copy of dolphin with the post processor option ?
Icon saying Partmaster Post processor ?
If so open it up and open the post file you are working with.
then under File right at the bottom it says compile, press that and it will generate the PPX file.
The PPR file is the readable version of the post processor.
The PPX file is the machine coded version of the same, each post has to have a PPR and PPX of the same name to work.