I just got a new MacBook Pro with Sierra (10.12.4). I transferred my Circus Ponies Notebooks (CPN) to the computer and the app is working in that I can open them and read them. But when I try to save, it says it can't. Read only. For one notebook only, it asked if I wanted to open it as read only or to make changes. I clicked "make changes" and now that one single notebook works. I have not been able to get that option to appear for any other notebook. I have also tried clicking "get info" and changing the permissions to "Read write" but even that has not worked. Other users have said CPN works on Sierra, so I know it's possible. Does anyone have suggestions?