It appears that there is an issue with the new compiler which we used for CM Note Keeper which prevents you from emptying the database.
A workaround would involved deleting the folder “com.completemagic.cmnotekeeper” located in username/Library/Application Support/ and starting the application again. Or just delete each note one at a time.
We will be releasing v1.0.4 within the next two weeks which would resolve this issue and also add RTF Import and Export feature.
We apologized for the inconvenience caused.