Hi there,
we have a github issue for Don’s finding and a more general one as well as an older forum thread.
Bottom line is: the v5 download contains a patched cpt4.jar file while the v4 download does not. A simpler approach than what Don has been doing is to download a v5 vocab file with only the CPT4 vocabulary checkbox marked for downloading. Then take the cpt4.jar file from this download and copy it over to your extracted v4 vocabulary folder to replace the one that came with it.