Well, I knew that I wouldn’t be able to sleep while thinking about the stuff above so I went back to the KN7000 and copied another floppy to the SD card. That changed the percent used to 1% instead of 0%. Not much improvement since it still is obviously wrong.

But, there is a way to delete an entire folder of the SD card. All you have to do is copy an empty floppy to the folder. That deletes all of the files of the folder. When I copied the empty floppy to the folder that I had just filled, the percent used went back to 0%. That must be a software glitch that needs fixing. It may have something to do with the fact that the KN7000 files are smaller (compressed) than the KN5000 files. When I edit the files and then save them in KN7000 format the space consumed is reduced on the SD card. That may confuse the algorhythm used in the "percent used" utility.