I've just upgraded to the current version - pluspak upgrade of my prior pluspak upgrades, but I've used BB continuously for many, many years, back to DOS, I believe, on my first PC, and switched to Mac when that was available. The old PC styles easily transferred to Mac. I never paid much attention to the total number of styles I had, till I was trying to figure out what to order this time and noticed that the included files in new versions totaled less than I had, which, again, have accumulated over the years. I haven't found any duplicates. Could it be that some old midi styles were replaced (by you) with newer styles, but I still have the old ones as well? Or my old PC styles are in the folder, somewhere? The original version of the program included, as well, an extensive fakebook of standards, which I still have. I imagine that was dropped due to copyright issues. Whatever, a great program, that has helped me learn to play, and the newest Mac version is a terrific upgrade.