PGALLDrumFolderNames.txt add your drums to the bottom of the list and save it, click Rebuild at the bottom of Drum Picker.
I made some Mac RealDrum Package Installers, but not on the Mac at the moment but I'm sure that was the file I had to update.
Also add info in DrumStylesInfo2.txt and RDUserMemos.txt then save.
I think they were in the Data folder ? will look and let you know.